Python报错‘attempted relative import beyond top-level package’，到底是因为什么？

快速了解Python相对导入

主要介绍了快速了解Python相对导入，具有一定借鉴价值,需要的朋友可以参考下

详解Python中的路径问题

主要介绍了Python中的路径问题，帮助大家更好的理解和学习python，感兴趣的朋友可以了解下

Python相对导入错误解析[项目源码]

本文详细解析了Python中相对导入时可能遇到的`ValueError: attempted relative import beyond top-level package`错误。通过一个具体的项目结构示例，展示了当尝试从顶层包之外进行相对导入时的问题。文章指出，Python不会将包含主入口文件（如server.py）的目录视为一个包，即使该目录包含`__init__.py`文件。因此，相对导入在这种情况下会失败。解决方案是使用绝对导入，或者在同一个包内进行相对导入。文章还提供了修改后的代码示例，展示了如何正确使用绝对导入来避免此类错误，并对比了在同一个包内成功使用相对导入的情况。

python3.6.5参考手册 chm

Python参考手册，官方正式版参考手册，chm版。以下摘取部分内容:Navigation index modules | next | Python » 3.6.5 Documentation » Python Documentation contents What’s New in Python What’s New In Python 3.6 Summary – Release highlights New Features PEP 498: Formatted string literals PEP 526: Syntax for variable annotations PEP 515: Underscores in Numeric Literals PEP 525: Asynchronous Generators PEP 530: Asynchronous Comprehensions PEP 487: Simpler customization of class creation PEP 487: Descriptor Protocol Enhancements PEP 519: Adding a file system path protocol PEP 495: Local Time Disambiguation PEP 529: Change Windows filesystem encoding to UTF-8 PEP 528: Change Windows console encoding to UTF-8 PEP 520: Preserving Class Attribute Definition Order PEP 468: Preserving Keyword Argument Order New dict implementation PEP 523: Adding a frame evaluation API to CPython PYTHONMALLOC environment variable DTrace and SystemTap probing support Other Language Changes New Modules secrets Improved Modules array ast asyncio binascii cmath collections concurrent.futures contextlib datetime decimal distutils email encodings enum faulthandler fileinput hashlib http.client idlelib and IDLE importlib inspect json logging math multiprocessing os pathlib pdb pickle pickletools pydoc random re readline rlcompleter shlex site sqlite3 socket socketserver ssl statistics struct subprocess sys telnetlib time timeit tkinter traceback tracemalloc typing unicodedata unittest.mock urllib.request urllib.robotparser venv warnings winreg winsound xmlrpc.client zipfile zlib Optimizations Build and C API Changes Other Improvements Deprecated New Keywords Deprecated Python behavior Deprecated Python modules, functions and methods asynchat asyncore dbm distutils grp importlib os re ssl tkinter venv Deprecated functions and types of the C API Deprecated Build Options Removed API and Feature Removals Porting to Python 3.6 Changes in ‘python’ Command Behavior Changes in the Python API Changes in the C API CPython bytecode changes Notable changes in Python 3.6.2 New make regen-all build target Removal of make touch build target Notable changes in Python 3.6.5 What’s New In Python 3.5 Summary – Release highlights New Features PEP 492 - Coroutines with async and await syntax PEP 465 - A dedicated infix operator for matrix multiplication PEP 448 - Additional Unpacking Generalizations PEP 461 - percent formatting support for bytes and bytearray PEP 484 - Type Hints PEP 471 - os.scandir() function – a better and faster directory iterator PEP 475: Retry system calls failing with EINTR PEP 479: Change StopIteration handling inside generators PEP 485: A function for testing approximate equality PEP 486: Make the Python Launcher aware of virtual environments PEP 488: Elimination of PYO files PEP 489: Multi-phase extension module initialization Other Language Changes New Modules typing zipapp Improved Modules argparse asyncio bz2 cgi cmath code collections collections.abc compileall concurrent.futures configparser contextlib csv curses dbm difflib distutils doctest email enum faulthandler functools glob gzip heapq http http.client idlelib and IDLE imaplib imghdr importlib inspect io ipaddress json linecache locale logging lzma math multiprocessing operator os pathlib pickle poplib re readline selectors shutil signal smtpd smtplib sndhdr socket ssl Memory BIO Support Application-Layer Protocol Negotiation Support Other Changes sqlite3 subprocess sys sysconfig tarfile threading time timeit tkinter traceback types unicodedata unittest unittest.mock urllib wsgiref xmlrpc xml.sax zipfile Other module-level changes Optimizations Build and C API Changes Deprecated New Keywords Deprecated Python Behavior Unsupported Operating Systems Deprecated Python modules, functions and methods Removed API and Feature Removals Porting to Python 3.5 Changes in Python behavior Changes in the Python API Changes in the C API What’s New In Python 3.4 Summary – Release Highlights New Features PEP 453: Explicit Bootstrapping of PIP in Python Installations Bootstrapping pip By Default Documentation Changes PEP 446: Newly Created File Descriptors Are Non-Inheritable Improvements to Codec Handling PEP 451: A ModuleSpec Type for the Import System Other Language Changes New Modules asyncio ensurepip enum pathlib selectors statistics tracemalloc Improved Modules abc aifc argparse audioop base64 collections colorsys contextlib dbm dis doctest email filecmp functools gc glob hashlib hmac html http idlelib and IDLE importlib inspect ipaddress logging marshal mmap multiprocessing operator os pdb pickle plistlib poplib pprint pty pydoc re resource select shelve shutil smtpd smtplib socket sqlite3 ssl stat struct subprocess sunau sys tarfile textwrap threading traceback types urllib unittest venv wave weakref xml.etree zipfile CPython Implementation Changes PEP 445: Customization of CPython Memory Allocators PEP 442: Safe Object Finalization PEP 456: Secure and Interchangeable Hash Algorithm PEP 436: Argument Clinic Other Build and C API Changes Other Improvements Significant Optimizations Deprecated Deprecations in the Python API Deprecated Features Removed Operating Systems No Longer Supported API and Feature Removals Code Cleanups Porting to Python 3.4 Changes in ‘python’ Command Behavior Changes in the Python API Changes in the C API Changed in 3.4.3 PEP 476: Enabling certificate verification by default for stdlib http clients What’s New In Python 3.3 Summary – Release highlights PEP 405: Virtual Environments PEP 420: Implicit Namespace Packages PEP 3118: New memoryview implementation and buffer protocol documentation Features API changes PEP 393: Flexible String Representation Functionality Performance and resource usage PEP 397: Python Launcher for Windows PEP 3151: Reworking the OS and IO exception hierarchy PEP 380: Syntax for Delegating to a Subgenerator PEP 409: Suppressing exception context PEP 414: Explicit Unicode literals PEP 3155: Qualified name for classes and functions PEP 412: Key-Sharing Dictionary PEP 362: Function Signature Object PEP 421: Adding sys.implementation SimpleNamespace Using importlib as the Implementation of Import New APIs Visible Changes Other Language Changes A Finer-Grained Import Lock Builtin functions and types New Modules faulthandler ipaddress lzma Improved Modules abc array base64 binascii bz2 codecs collections contextlib crypt curses datetime decimal Features API changes email Policy Framework Provisional Policy with New Header API Other API Changes ftplib functools gc hmac http html imaplib inspect io itertools logging math mmap multiprocessing nntplib os pdb pickle pydoc re sched select shlex shutil signal smtpd smtplib socket socketserver sqlite3 ssl stat struct subprocess sys tarfile tempfile textwrap threading time types unittest urllib webbrowser xml.etree.ElementTree zlib Optimizations Build and C API Changes Deprecated Unsupported Operating Systems Deprecated Python modules, functions and methods Deprecated functions and types of the C API Deprecated features Porting to Python 3.3 Porting Python code Porting C code Building C extensions Command Line Switch Changes What’s New In Python 3.2 PEP 384: Defining a Stable ABI PEP 389: Argparse Command Line Parsing Module PEP 391: Dictionary Based Configuration for Logging PEP 3148: The concurrent.futures module PEP 3147: PYC Repository Directories PEP 3149: ABI Version Tagged .so Files PEP 3333: Python Web Server Gateway Interface v1.0.1 Other Language Changes New, Improved, and Deprecated Modules email elementtree functools itertools collections threading datetime and time math abc io reprlib logging csv contextlib decimal and fractions ftp popen select gzip and zipfile tarfile hashlib ast os shutil sqlite3 html socket ssl nntp certificates imaplib http.client unittest random poplib asyncore tempfile inspect pydoc dis dbm ctypes site sysconfig pdb configparser urllib.parse mailbox turtledemo Multi-threading Optimizations Unicode Codecs Documentation IDLE Code Repository Build and C API Changes Porting to Python 3.2 What’s New In Python 3.1 PEP 372: Ordered Dictionaries PEP 378: Format Specifier for Thousands Separator Other Language Changes New, Improved, and Deprecated Modules Optimizations IDLE Build and C API Changes Porting to Python 3.1 What’s New In Python 3.0 Common Stumbling Blocks Print Is A Function Views And Iterators Instead Of Lists Ordering Comparisons Integers Text Vs. Data Instead Of Unicode Vs. 8-bit Overview Of Syntax Changes New Syntax Changed Syntax Removed Syntax Changes Already Present In Python 2.6 Library Changes PEP 3101: A New Approach To String Formatting Changes To Exceptions Miscellaneous Other Changes Operators And Special Methods Builtins Build and C API Changes Performance Porting To Python 3.0 What’s New in Python 2.7 The Future for Python 2.x Changes to the Handling of Deprecation Warnings Python 3.1 Features PEP 372: Adding an Ordered Dictionary to collections PEP 378: Format Specifier for Thousands Separator PEP 389: The argparse Module for Parsing Command Lines PEP 391: Dictionary-Based Configuration For Logging PEP 3106: Dictionary Views PEP 3137: The memoryview Object Other Language Changes Interpreter Changes Optimizations New and Improved Modules New module: importlib New module: sysconfig ttk: Themed Widgets for Tk Updated module: unittest Updated module: ElementTree 1.3 Build and C API Changes Capsules Port-Specific Changes: Windows Port-Specific Changes: Mac OS X Port-Specific Changes: FreeBSD Other Changes and Fixes Porting to Python 2.7 New Features Added to Python 2.7 Maintenance Releases PEP 434: IDLE Enhancement Exception for All Branches PEP 466: Network Security Enhancements for Python 2.7 Acknowledgements What’s New in Python 2.6 Python 3.0 Changes to the Development Process New Issue Tracker: Roundup New Documentation Format: reStructuredText Using Sphinx PEP 343: The ‘with’ statement Writing Context Managers The contextlib module PEP 366: Explicit Relative Imports From a Main Module PEP 370: Per-user site-packages Directory PEP 371: The multiprocessing Package PEP 3101: Advanced String Formatting PEP 3105: print As a Function PEP 3110: Exception-Handling Changes PEP 3112: Byte Literals PEP 3116: New I/O Library PEP 3118: Revised Buffer Protocol PEP 3119: Abstract Base Classes PEP 3127: Integer Literal Support and Syntax PEP 3129: Class Decorators PEP 3141: A Type Hierarchy for Numbers The fractions Module Other Language Changes Optimizations Interpreter Changes New and Improved Modules The ast module The future_builtins module The json module: JavaScript Object Notation The plistlib module: A Property-List Parser ctypes Enhancements Improved SSL Support Deprecations and Removals Build and C API Changes Port-Specific Changes: Windows Port-Specific Changes: Mac OS X Port-Specific Changes: IRIX Porting to Python 2.6 Acknowledgements What’s New in Python 2.5 PEP 308: Conditional Expressions PEP 309: Partial Function Application PEP 314: Metadata for Python Software Packages v1.1 PEP 328: Absolute and Relative Imports PEP 338: Executing Modules as Scripts PEP 341: Unified try/except/finally PEP 342: New Generator Features PEP 343: The ‘with’ statement Writing Context Managers The contextlib module PEP 352: Exceptions as New-Style Classes PEP 353: Using ssize_t as the index type PEP 357: The ‘__index__’ method Other Language Changes Interactive Interpreter Changes Optimizations New, Improved, and Removed Modules The ctypes package The ElementTree package The hashlib package The sqlite3 package The wsgiref package Build and C API Changes Port-Specific Changes Porting to Python 2.5 Acknowledgements What’s New in Python 2.4 PEP 218: Built-In Set Objects PEP 237: Unifying Long Integers and Integers PEP 289: Generator Expressions PEP 292: Simpler String Substitutions PEP 318: Decorators for Functions and Methods PEP 322: Reverse Iteration PEP 324: New subprocess Module PEP 327: Decimal Data Type Why is Decimal needed? The Decimal type The Context type PEP 328: Multi-line Imports PEP 331: Locale-Independent Float/String Conversions Other Language Changes Optimizations New, Improved, and Deprecated Modules cookielib doctest Build and C API Changes Port-Specific Changes Porting to Python 2.4 Acknowledgements What’s New in Python 2.3 PEP 218: A Standard Set Datatype PEP 255: Simple Generators PEP 263: Source Code Encodings PEP 273: Importing Modules from ZIP Archives PEP 277: Unicode file name support for Windows NT PEP 278: Universal Newline Support PEP 279: enumerate() PEP 282: The logging Package PEP 285: A Boolean Type PEP 293: Codec Error Handling Callbacks PEP 301: Package Index and Metadata for Distutils PEP 302: New Import Hooks PEP 305: Comma-separated Files PEP 307: Pickle Enhancements Extended Slices Other Language Changes String Changes Optimizations New, Improved, and Deprecated Modules Date/Time Type The optparse Module Pymalloc: A Specialized Object Allocator Build and C API Changes Port-Specific Changes Other Changes and Fixes Porting to Python 2.3 Acknowledgements What’s New in Python 2.2 Introduction PEPs 252 and 253: Type and Class Changes Old and New Classes Descriptors Multiple Inheritance: The Diamond Rule Attribute Access Related Links PEP 234: Iterators PEP 255: Simple Generators PEP 237: Unifying Long Integers and Integers PEP 238: Changing the Division Operator Unicode Changes PEP 227: Nested Scopes New and Improved Modules Interpreter Changes and Fixes Other Changes and Fixes Acknowledgements What’s New in Python 2.1 Introduction PEP 227: Nested Scopes PEP 236: __future__ Directives PEP 207: Rich Comparisons PEP 230: Warning Framework PEP 229: New Build System PEP 205: Weak References PEP 232: Function Attributes PEP 235: Importing Modules on Case-Insensitive Platforms PEP 217: Interactive Display Hook PEP 208: New Coercion Model PEP 241: Metadata in Python Packages New and Improved Modules Other Changes and Fixes Acknowledgements What’s New in Python 2.0 Introduction What About Python 1.6? New Development Process Unicode List Comprehensions Augmented Assignment String Methods Garbage Collection of Cycles Other Core Changes Minor Language Changes Changes to Built-in Functions Porting to 2.0 Extending/Embedding Changes Distutils: Making Modules Easy to Install XML Modules SAX2 Support DOM Support Relationship to PyXML Module changes New modules IDLE Improvements Deleted and Deprecated Modules Acknowledgements Changelog Python 3.6.5 final? Tests Build Python 3.6.5 release candidate 1? Security Core and Builtins Library Documentation Tests Build Windows macOS IDLE Tools/Demos C API Python 3.6.4 final? Python 3.6.4 release candidate 1? Core and Builtins Library Documentation Tests Build Windows macOS IDLE Tools/Demos C API Python 3.6.3 final? Library Build Python 3.6.3 release candidate 1? Security Core and Builtins Library Documentation Tests Build Windows IDLE Tools/Demos Python 3.6.2 final? Python 3.6.2 release candidate 2? Security Python 3.6.2 release candidate 1? Core and Builtins Library Security Library IDLE C API Build Documentation Tools/Demos Tests Windows Python 3.6.1 final? Core and Builtins Build Python 3.6.1 release candidate 1? Core and Builtins Library IDLE Windows C API Documentation Tests Build Python 3.6.0 final? Python 3.6.0 release candidate 2? Core and Builtins Tools/Demos Windows Build Python 3.6.0 release candidate 1? Core and Builtins Library C API Documentation Tools/Demos Python 3.6.0 beta 4? Core and Builtins Library Documentation Tests Build Python 3.6.0 beta 3? Core and Builtins Library Windows Build Tests Python 3.6.0 beta 2? Core and Builtins Library Windows C API Build Tests Python 3.6.0 beta 1? Core and Builtins Library IDLE C API Tests Build Tools/Demos Windows Python 3.6.0 alpha 4? Core and Builtins Library IDLE Tests Windows Build Python 3.6.0 alpha 3? Core and Builtins Library Security Library Security Library IDLE C API Build Tools/Demos Documentation Tests Python 3.6.0 alpha 2? Core and Builtins Library Security Library Security Library IDLE Documentation Tests Windows Build Windows C API Tools/Demos Python 3.6.0 alpha 1? Core and Builtins Library Security Library Security Library Security Library IDLE Documentation Tests Build Windows Tools/Demos C API Python 3.5.3 final? Python 3.5.3 release candidate 1? Core and Builtins Library Security Library Security Library IDLE C API Documentation Tests Tools/Demos Windows Build Python 3.5.2 final? Core and Builtins Tests IDLE Python 3.5.2 release candidate 1? Core and Builtins Security Library Security Library Security Library Security Library Security Library IDLE Documentation Tests Build Windows Tools/Demos Windows Python 3.5.1 final? Core and Builtins Windows Python 3.5.1 release candidate 1? Core and Builtins Library IDLE Documentation Tests Build Windows Tools/Demos Python 3.5.0 final? Build Python 3.5.0 release candidate 4? Library Build Python 3.5.0 release candidate 3? Core and Builtins Library Python 3.5.0 release candidate 2? Core and Builtins Library Python 3.5.0 release candidate 1? Core and Builtins Library IDLE Documentation Tests Python 3.5.0 beta 4? Core and Builtins Library Build Python 3.5.0 beta 3? Core and Builtins Library Tests Documentation Build Python 3.5.0 beta 2? Core and Builtins Library Python 3.5.0 beta 1? Core and Builtins Library IDLE Tests Documentation Tools/Demos Python 3.5.0 alpha 4? Core and Builtins Library Build Tests Tools/Demos C API Python 3.5.0 alpha 3? Core and Builtins Library Build Tests Tools/Demos Python 3.5.0 alpha 2? Core and Builtins Library Build C API Windows Python 3.5.0 alpha 1? Core and Builtins Library IDLE Build C API Documentation Tests Tools/Demos Windows The Python Tutorial 1. Whetting Your Appetite 2. Using the Python Interpreter 2.1. Invoking the Interpreter 2.1.1. Argument Passing 2.1.2. Interactive Mode 2.2. The Interpreter and Its Environment 2.2.1. Source Code Encoding 3. An Informal Introduction to Python 3.1. Using Python as a Calculator 3.1.1. Numbers 3.1.2. Strings 3.1.3. Lists 3.2. First Steps Towards Programming 4. More Control Flow Tools 4.1. if Statements 4.2. for Statements 4.3. The range() Function 4.4. break and continue Statements, and else Clauses on Loops 4.5. pass Statements 4.6. Defining Functions 4.7. More on Defining Functions 4.7.1. Default Argument Values 4.7.2. Keyword Arguments 4.7.3. Arbitrary Argument Lists 4.7.4. Unpacking Argument Lists 4.7.5. Lambda Expressions 4.7.6. Documentation Strings 4.7.7. Function Annotations 4.8. Intermezzo: Coding Style 5. Data Structures 5.1. More on Lists 5.1.1. Using Lists as Stacks 5.1.2. Using Lists as Queues 5.1.3. List Comprehensions 5.1.4. Nested List Comprehensions 5.2. The del statement 5.3. Tuples and Sequences 5.4. Sets 5.5. Dictionaries 5.6. Looping Techniques 5.7. More on Conditions 5.8. Comparing Sequences and Other Types 6. Modules 6.1. More on Modules 6.1.1. Executing modules as scripts 6.1.2. The Module Search Path 6.1.3. “Compiled” Python files 6.2. Standard Modules 6.3. The dir() Function 6.4. Packages 6.4.1. Importing * From a Package 6.4.2. Intra-package References 6.4.3. Packages in Multiple Directories 7. Input and Output 7.1. Fancier Output Formatting 7.1.1. Old string formatting 7.2. Reading and Writing Files 7.2.1. Methods of File Objects 7.2.2. Saving structured data with json 8. Errors and Exceptions 8.1. Syntax Errors 8.2. Exceptions 8.3. Handling Exceptions 8.4. Raising Exceptions 8.5. User-defined Exceptions 8.6. Defining Clean-up Actions 8.7. Predefined Clean-up Actions 9. Classes 9.1. A Word About Names and Objects 9.2. Python Scopes and Namespaces 9.2.1. Scopes and Namespaces Example 9.3. A First Look at Classes 9.3.1. Class Definition Syntax 9.3.2. Class Objects 9.3.3. Instance Objects 9.3.4. Method Objects 9.3.5. Class and Instance Variables 9.4. Random Remarks 9.5. Inheritance 9.5.1. Multiple Inheritance 9.6. Private Variables 9.7. Odds and Ends 9.8. Iterators 9.9. Generators 9.10. Generator Expressions 10. Brief Tour of the Standard Library 10.1. Operating System Interface 10.2. File Wildcards 10.3. Command Line Arguments 10.4. Error Output Redirection and Program Termination 10.5. String Pattern Matching 10.6. Mathematics 10.7. Internet Access 10.8. Dates and Times 10.9. Data Compression 10.10. Performance Measurement 10.11. Quality Control 10.12. Batteries Included 11. Brief Tour of the Standard Library — Part II 11.1. Output Formatting 11.2. Templating 11.3. Working with Binary Data Record Layouts 11.4. Multi-threading 11.5. Logging 11.6. Weak References 11.7. Tools for Working with Lists 11.8. Decimal Floating Point Arithmetic 12. Virtual Environments and Packages 12.1. Introduction 12.2. Creating Virtual Environments 12.3. Managing Packages with pip 13. What Now? 14. Interactive Input Editing and History Substitution 14.1. Tab Completion and History Editing 14.2. Alternatives to the Interactive Interpreter 15. Floating Point Arithmetic: Issues and Limitations 15.1. Representation Error 16. Appendix 16.1. Interactive Mode 16.1.1. Error Handling 16.1.2. Executable Python Scripts 16.1.3. The Interactive Startup File 16.1.4. The Customization Modules Python Setup and Usage 1. Command line and environment 1.1. Command line 1.1.1. Interface options 1.1.2. Generic options 1.1.3. Miscellaneous options 1.1.4. Options you shouldn’t use 1.2. Environment variables 1.2.1. Debug-mode variables 2. Using Python on Unix platforms 2.1. Getting and installing the latest version of Python 2.1.1. On Linux 2.1.2. On FreeBSD and OpenBSD 2.1.3. On OpenSolaris 2.2. Building Python 2.3. Python-related paths and files 2.4. Miscellaneous 2.5. Editors and IDEs 3. Using Python on Windows 3.1. Installing Python 3.1.1. Supported Versions 3.1.2. Installation Steps 3.1.3. Removing the MAX_PATH Limitation 3.1.4. Installing Without UI 3.1.5. Installing Without Downloading 3.1.6. Modifying an install 3.1.7. Other Platforms 3.2. Alternative bundles 3.3. Configuring Python 3.3.1. Excursus: Setting environment variables 3.3.2. Finding the Python executable 3.4. Python Launcher for Windows 3.4.1. Getting started 3.4.1.1. From the command-line 3.4.1.2. Virtual environments 3.4.1.3. From a script 3.4.1.4. From file associations 3.4.2. Shebang Lines 3.4.3. Arguments in shebang lines 3.4.4. Customization 3.4.4.1. Customization via INI files 3.4.4.2. Customizing default Python versions 3.4.5. Diagnostics 3.5. Finding modules 3.6. Additional modules 3.6.1. PyWin32 3.6.2. cx_Freeze 3.6.3. WConio 3.7. Compiling Python on Windows 3.8. Embedded Distribution 3.8.1. Python Application 3.8.2. Embedding Python 3.9. Other resources 4. Using Python on a Macintosh 4.1. Getting and Installing MacPython 4.1.1. How to run a Python script 4.1.2. Running scripts with a GUI 4.1.3. Configuration 4.2. The IDE 4.3. Installing Additional Python Packages 4.4. GUI Programming on the Mac 4.5. Distributing Python Applications on the Mac 4.6. Other Resources The Python Language Reference 1. Introduction 1.1. Alternate Implementations 1.2. Notation 2. Lexical analysis 2.1. Line structure 2.1.1. Logical lines 2.1.2. Physical lines 2.1.3. Comments 2.1.4. Encoding declarations 2.1.5. Explicit line joining 2.1.6. Implicit line joining 2.1.7. Blank lines 2.1.8. Indentation 2.1.9. Whitespace between tokens 2.2. Other tokens 2.3. Identifiers and keywords 2.3.1. Keywords 2.3.2. Reserved classes of identifiers 2.4. Literals 2.4.1. String and Bytes literals 2.4.2. String literal concatenation 2.4.3. Formatted string literals 2.4.4. Numeric literals 2.4.5. Integer literals 2.4.6. Floating point literals 2.4.7. Imaginary literals 2.5. Operators 2.6. Delimiters 3. Data model 3.1. Objects, values and types 3.2. The standard type hierarchy 3.3. Special method names 3.3.1. Basic customization 3.3.2. Customizing attribute access 3.3.2.1. Customizing module attribute access 3.3.2.2. Implementing Descriptors 3.3.2.3. Invoking Descriptors 3.3.2.4. __slots__ 3.3.2.4.1. Notes on using __slots__ 3.3.3. Customizing class creation 3.3.3.1. Metaclasses 3.3.3.2. Determining the appropriate metaclass 3.3.3.3. Preparing the class namespace 3.3.3.4. Executing the class body 3.3.3.5. Creating the class object 3.3.3.6. Metaclass example 3.3.4. Customizing instance and subclass checks 3.3.5. Emulating callable objects 3.3.6. Emulating container types 3.3.7. Emulating numeric types 3.3.8. With Statement Context Managers 3.3.9. Special method lookup 3.4. Coroutines 3.4.1. Awaitable Objects 3.4.2. Coroutine Objects 3.4.3. Asynchronous Iterators 3.4.4. Asynchronous Context Managers 4. Execution model 4.1. Structure of a program 4.2. Naming and binding 4.2.1. Binding of names 4.2.2. Resolution of names 4.2.3. Builtins and restricted execution 4.2.4. Interaction with dynamic features 4.3. Exceptions 5. The import system 5.1. importlib 5.2. Packages 5.2.1. Regular packages 5.2.2. Namespace packages 5.3. Searching 5.3.1. The module cache 5.3.2. Finders and loaders 5.3.3. Import hooks 5.3.4. The meta path 5.4. Loading 5.4.1. Loaders 5.4.2. Submodules 5.4.3. Module spec 5.4.4. Import-related module attributes 5.4.5. module.__path__ 5.4.6. Module reprs 5.5. The Path Based Finder 5.5.1. Path entry finders 5.5.2. Path entry finder protocol 5.6. Replacing the standard import system 5.7. Special considerations for __main__ 5.7.1. __main__.__spec__ 5.8. Open issues 5.9. References 6. Expressions 6.1. Arithmetic conversions 6.2. Atoms 6.2.1. Identifiers (Names) 6.2.2. Literals 6.2.3. Parenthesized forms 6.2.4. Displays for lists, sets and dictionaries 6.2.5. List displays 6.2.6. Set displays 6.2.7. Dictionary displays 6.2.8. Generator expressions 6.2.9. Yield expressions 6.2.9.1. Generator-iterator methods 6.2.9.2. Examples 6.2.9.3. Asynchronous generator functions 6.2.9.4. Asynchronous generator-iterator methods 6.3. Primaries 6.3.1. Attribute references 6.3.2. Subscriptions 6.3.3. Slicings 6.3.4. Calls 6.4. Await expression 6.5. The power operator 6.6. Unary arithmetic and bitwise operations 6.7. Binary arithmetic operations 6.8. Shifting operations 6.9. Binary bitwise operations 6.10. Comparisons 6.10.1. Value comparisons 6.10.2. Membership test operations 6.10.3. Identity comparisons 6.11. Boolean operations 6.12. Conditional expressions 6.13. Lambdas 6.14. Expression lists 6.15. Evaluation order 6.16. Operator precedence 7. Simple statements 7.1. Expression statements 7.2. Assignment statements 7.2.1. Augmented assignment statements 7.2.2. Annotated assignment statements 7.3. The assert statement 7.4. The pass statement 7.5. The del statement 7.6. The return statement 7.7. The yield statement 7.8. The raise statement 7.9. The break statement 7.10. The continue statement 7.11. The import statement 7.11.1. Future statements 7.12. The global statement 7.13. The nonlocal statement 8. Compound statements 8.1. The if statement 8.2. The while statement 8.3. The for statement 8.4. The try statement 8.5. The with statement 8.6. Function definitions 8.7. Class definitions 8.8. Coroutines 8.8.1. Coroutine function definition 8.8.2. The async for statement 8.8.3. The async with statement 9. Top-level components 9.1. Complete Python programs 9.2. File input 9.3. Interactive input 9.4. Expression input 10. Full Grammar specification The Python Standard Library 1. Introduction 2. Built-in Functions 3. Built-in Constants 3.1. Constants added by the site module 4. Built-in Types 4.1. Truth Value Testing 4.2. Boolean Operations — and, or, not 4.3. Comparisons 4.4. Numeric Types — int, float, complex 4.4.1. Bitwise Operations on Integer Types 4.4.2. Additional Methods on Integer Types 4.4.3. Additional Methods on Float 4.4.4. Hashing of numeric types 4.5. Iterator Types 4.5.1. Generator Types 4.6. Sequence Types — list, tuple, range 4.6.1. Common Sequence Operations 4.6.2. Immutable Sequence Types 4.6.3. Mutable Sequence Types 4.6.4. Lists 4.6.5. Tuples 4.6.6. Ranges 4.7. Text Sequence Type — str 4.7.1. String Methods 4.7.2. printf-style String Formatting 4.8. Binary Sequence Types — bytes, bytearray, memoryview 4.8.1. Bytes Objects 4.8.2. Bytearray Objects 4.8.3. Bytes and Bytearray Operations 4.8.4. printf-style Bytes Formatting 4.8.5. Memory Views 4.9. Set Types — set, frozenset 4.10. Mapping Types — dict 4.10.1. Dictionary view objects 4.11. Context Manager Types 4.12. Other Built-in Types 4.12.1. Modules 4.12.2. Classes and Class Instances 4.12.3. Functions 4.12.4. Methods 4.12.5. Code Objects 4.12.6. Type Objects 4.12.7. The Null Object 4.12.8. The Ellipsis Object 4.12.9. The NotImplemented Object 4.12.10. Boolean Values 4.12.11. Internal Objects 4.13. Special Attributes 5. Built-in Exceptions 5.1. Base classes 5.2. Concrete exceptions 5.2.1. OS exceptions 5.3. Warnings 5.4. Exception hierarchy 6. Text Processing Services 6.1. string — Common string operations 6.1.1. String constants 6.1.2. Custom String Formatting 6.1.3. Format String Syntax 6.1.3.1. Format Specification Mini-Language 6.1.3.2. Format examples 6.1.4. Template strings 6.1.5. Helper functions 6.2. re — Regular expression operations 6.2.1. Regular Expression Syntax 6.2.2. Module Contents 6.2.3. Regular Expression Objects 6.2.4. Match Objects 6.2.5. Regular Expression Examples 6.2.5.1. Checking for a Pair 6.2.5.2. Simulating scanf() 6.2.5.3. search() vs. match() 6.2.5.4. Making a Phonebook 6.2.5.5. Text Munging 6.2.5.6. Finding all Adverbs 6.2.5.7. Finding all Adverbs and their Positions 6.2.5.8. Raw String Notation 6.2.5.9. Writing a Tokenizer 6.3. difflib — Helpers for computing deltas 6.3.1. SequenceMatcher Objects 6.3.2. SequenceMatcher Examples 6.3.3. Differ Objects 6.3.4. Differ Example 6.3.5. A command-line interface to difflib 6.4. textwrap — Text wrapping and filling 6.5. unicodedata — Unicode Database 6.6. stringprep — Internet String Preparation 6.7. readline — GNU readline interface 6.7.1. Init file 6.7.2. Line buffer 6.7.3. History file 6.7.4. History list 6.7.5. Startup hooks 6.7.6. Completion 6.7.7. Example 6.8. rlcompleter — Completion function for GNU readline 6.8.1. Completer Objects 7. Binary Data Services 7.1. struct — Interpret bytes as packed binary data 7.1.1. Functions and Exceptions 7.1.2. Format Strings 7.1.2.1. Byte Order, Size, and Alignment 7.1.2.2. Format Characters 7.1.2.3. Examples 7.1.3. Classes 7.2. codecs — Codec registry and base classes 7.2.1. Codec Base Classes 7.2.1.1. Error Handlers 7.2.1.2. Stateless Encoding and Decoding 7.2.1.3. Incremental Encoding and Decoding 7.2.1.3.1. IncrementalEncoder Objects 7.2.1.3.2. IncrementalDecoder Objects 7.2.1.4. Stream Encoding and Decoding 7.2.1.4.1. StreamWriter Objects 7.2.1.4.2. StreamReader Objects 7.2.1.4.3. StreamReaderWriter Objects 7.2.1.4.4. StreamRecoder Objects 7.2.2. Encodings and Unicode 7.2.3. Standard Encodings 7.2.4. Python Specific Encodings 7.2.4.1. Text Encodings 7.2.4.2. Binary Transforms 7.2.4.3. Text Transforms 7.2.5. encodings.idna — Internationalized Domain Names in Applications 7.2.6. encodings.mbcs — Windows ANSI codepage 7.2.7. encodings.utf_8_sig — UTF-8 codec with BOM signature 8. Data Types 8.1. datetime — Basic date and time types 8.1.1. Available Types 8.1.2. timedelta Objects 8.1.3. date Objects 8.1.4. datetime Objects 8.1.5. time Objects 8.1.6. tzinfo Objects 8.1.7. timezone Objects 8.1.8. strftime() and strptime() Behavior 8.2. calendar — General calendar-related functions 8.3. collections — Container datatypes 8.3.1. ChainMap objects 8.3.1.1. ChainMap Examples and Recipes 8.3.2. Counter objects 8.3.3. deque objects 8.3.3.1. deque Recipes 8.3.4. defaultdict objects 8.3.4.1. defaultdict Examples 8.3.5. namedtuple() Factory Function for Tuples with Named Fields 8.3.6. OrderedDict objects 8.3.6.1. OrderedDict Examples and Recipes 8.3.7. UserDict objects 8.3.8. UserList objects 8.3.9. UserString objects 8.4. collections.abc — Abstract Base Classes for Containers 8.4.1. Collections Abstract Base Classes 8.5. heapq — Heap queue algorithm 8.5.1. Basic Examples 8.5.2. Priority Queue Implementation Notes 8.5.3. Theory 8.6. bisect — Array bisection algorithm 8.6.1. Searching Sorted Lists 8.6.2. Other Examples 8.7. array — Efficient arrays of numeric values 8.8. weakref — Weak references 8.8.1. Weak Reference Objects 8.8.2. Example 8.8.3. Finalizer Objects 8.8.4. Comparing finalizers with __del__() methods 8.9. types — Dynamic type creation and names for built-in types 8.9.1. Dynamic Type Creation 8.9.2. Standard Interpreter Types 8.9.3. Additional Utility Classes and Functions 8.9.4. Coroutine Utility Functions 8.10. copy — Shallow and deep copy operations 8.11. pprint — Data pretty printer 8.11.1. PrettyPrinter Objects 8.11.2. Example 8.12. reprlib — Alternate repr() implementation 8.12.1. Repr Objects 8.12.2. Subclassing Repr Objects 8.13. enum — Support for enumerations 8.13.1. Module Contents 8.13.2. Creating an Enum 8.13.3. Programmatic access to enumeration members and their attributes 8.13.4. Duplicating enum members and values 8.13.5. Ensuring unique enumeration values 8.13.6. Using automatic values 8.13.7. Iteration 8.13.8. Comparisons 8.13.9. Allowed members and attributes of enumerations 8.13.10. Restricted subclassing of enumerations 8.13.11. Pickling 8.13.12. Functional API 8.13.13. Derived Enumerations 8.13.13.1. IntEnum 8.13.13.2. IntFlag 8.13.13.3. Flag 8.13.13.4. Others 8.13.14. Interesting examples 8.13.14.1. Omitting values 8.13.14.1.1. Using auto 8.13.14.1.2. Using object 8.13.14.1.3. Using a descriptive string 8.13.14.1.4. Using a custom __new__() 8.13.14.2. OrderedEnum 8.13.14.3. DuplicateFreeEnum 8.13.14.4. Planet 8.13.15. How are Enums different? 8.13.15.1. Enum Classes 8.13.15.2. Enum Members (aka instances) 8.13.15.3. Finer Points 8.13.15.3.1. Supported __dunder__ names 8.13.15.3.2. Supported _sunder_ names 8.13.15.3.3. Enum member type 8.13.15.3.4. Boolean value of Enum classes and members 8.13.15.3.5. Enum classes with methods 8.13.15.3.6. Combining members of Flag 9. Numeric and Mathematical Modules 9.1. numbers — Numeric abstract base classes 9.1.1. The numeric tower 9.1.2. Notes for type implementors 9.1.2.1. Adding More Numeric ABCs 9.1.2.2. Implementing the arithmetic operations 9.2. math — Mathematical functions 9.2.1. Number-theoretic and representation functions 9.2.2. Power and logarithmic functions 9.2.3. Trigonometric functions 9.2.4. Angular conversion 9.2.5. Hyperbolic functions 9.2.6. Special functions 9.2.7. Constants 9.3. cmath — Mathematical functions for complex numbers 9.3.1. Conversions to and from polar coordinates 9.3.2. Power and logarithmic functions 9.3.3. Trigonometric functions 9.3.4. Hyperbolic functions 9.3.5. Classification functions 9.3.6. Constants 9.4. decimal — Decimal fixed point and floating point arithmetic 9.4.1. Quick-start Tutorial 9.4.2. Decimal objects 9.4.2.1. Logical operands 9.4.3. Context objects 9.4.4. Constants 9.4.5. Rounding modes 9.4.6. Signals 9.4.7. Floating Point Notes 9.4.7.1. Mitigating round-off error with increased precision 9.4.7.2. Special values 9.4.8. Working with threads 9.4.9. Recipes 9.4.10. Decimal FAQ 9.5. fractions — Rational numbers 9.6. random — Generate pseudo-random numbers 9.6.1. Bookkeeping functions 9.6.2. Functions for integers 9.6.3. Functions for sequences 9.6.4. Real-valued distributions 9.6.5. Alternative Generator 9.6.6. Notes on Reproducibility 9.6.7. Examples and Recipes 9.7. statistics — Mathematical statistics functions 9.7.1. Averages and measures of central location 9.7.2. Measures of spread 9.7.3. Function details 9.7.4. Exceptions 10. Functional Programming Modules 10.1. itertools — Functions creating iterators for efficient looping 10.1.1. Itertool functions 10.1.2. Itertools Recipes 10.2. functools — Higher-order functions and operations on callable objects 10.2.1. partial Objects 10.3. operator — Standard operators as functions 10.3.1. Mapping Operators to Functions 10.3.2. Inplace Operators 11. File and Directory Access 11.1. pathlib — Object-oriented filesystem paths 11.1.1. Basic use 11.1.2. Pure paths 11.1.2.1. General properties 11.1.2.2. Operators 11.1.2.3. Accessing individual parts 11.1.2.4. Methods and properties 11.1.3. Concrete paths 11.1.3.1. Methods 11.2. os.path — Common pathname manipulations 11.3. fileinput — Iterate over lines from multiple input streams 11.4. stat — Interpreting stat() results 11.5. filecmp — File and Directory Comparisons 11.5.1. The dircmp class 11.6. tempfile — Generate temporary files and directories 11.6.1. Examples 11.6.2. Deprecated functions and variables 11.7. glob — Unix style pathname pattern expansion 11.8. fnmatch — Unix filename pattern matching 11.9. linecache — Random access to text lines 11.10. shutil — High-level file operations 11.10.1. Directory and files operations 11.10.1.1. copytree example 11.10.1.2. rmtree example 11.10.2. Archiving operations 11.10.2.1. Archiving example 11.10.3. Querying the size of the output terminal 11.11. macpath — Mac OS 9 path manipulation functions 12. Data Persistence 12.1. pickle — Python object serialization 12.1.1. Relationship to other Python modules 12.1.1.1. Comparison with marshal 12.1.1.2. Comparison with json 12.1.2. Data stream format 12.1.3. Module Interface 12.1.4. What can be pickled and unpickled? 12.1.5. Pickling Class Instances 12.1.5.1. Persistence of External Objects 12.1.5.2. Dispatch Tables 12.1.5.3. Handling Stateful Objects 12.1.6. Restricting Globals 12.1.7. Performance 12.1.8. Examples 12.2. copyreg — Register pickle support functions 12.2.1. Example 12.3. shelve — Python object persistence 12.3.1. Restrictions 12.3.2. Example 12.4. marshal — Internal Python object serialization 12.5. dbm — Interfaces to Unix “databases” 12.5.1. dbm.gnu — GNU’s reinterpretation of dbm 12.5.2. dbm.ndbm — Interface based on ndbm 12.5.3. dbm.dumb — Portable DBM implementation 12.6. sqlite3 — DB-API 2.0 interface for SQLite databases 12.6.1. Module functions and constants 12.6.2. Connection Objects 12.6.3. Cursor Objects 12.6.4. Row Objects 12.6.5. Exceptions 12.6.6. SQLite and Python types 12.6.6.1. Introduction 12.6.6.2. Using adapters to store additional Python types in SQLite databases 12.6.6.2.1. Letting your object adapt itself 12.6.6.2.2. Registering an adapter callable 12.6.6.3. Converting SQLite values to custom Python types 12.6.6.4. Default adapters and converters 12.6.7. Controlling Transactions 12.6.8. Using sqlite3 efficiently 12.6.8.1. Using shortcut methods 12.6.8.2. Accessing columns by name instead of by index 12.6.8.3. Using the connection as a context manager 12.6.9. Common issues 12.6.9.1. Multithreading 13. Data Compression and Archiving 13.1. zlib — Compression compatible with gzip 13.2. gzip — Support for gzip files 13.2.1. Examples of usage 13.3. bz2 — Support for bzip2 compression 13.3.1. (De)compression of files 13.3.2. Incremental (de)compression 13.3.3. One-shot (de)compression 13.4. lzma — Compression using the LZMA algorithm 13.4.1. Reading and writing compressed files 13.4.2. Compressing and decompressing data in memory 13.4.3. Miscellaneous 13.4.4. Specifying custom filter chains 13.4.5. Examples 13.5. zipfile — Work with ZIP archives 13.5.1. ZipFile Objects 13.5.2. PyZipFile Objects 13.5.3. ZipInfo Objects 13.5.4. Command-Line Interface 13.5.4.1. Command-line options 13.6. tarfile — Read and write tar archive files 13.6.1. TarFile Objects 13.6.2. TarInfo Objects 13.6.3. Command-Line Interface 13.6.3.1. Command-line options 13.6.4. Examples 13.6.5. Supported tar formats 13.6.6. Unicode issues 14. File Formats 14.1. csv — CSV File Reading and Writing 14.1.1. Module Contents 14.1.2. Dialects and Formatting Parameters 14.1.3. Reader Objects 14.1.4. Writer Objects 14.1.5. Examples 14.2. configparser — Configuration file parser 14.2.1. Quick Start 14.2.2. Supported Datatypes 14.2.3. Fallback Values 14.2.4. Supported INI File Structure 14.2.5. Interpolation of values 14.2.6. Mapping Protocol Access 14.2.7. Customizing Parser Behaviour 14.2.8. Legacy API Examples 14.2.9. ConfigParser Objects 14.2.10. RawConfigParser Objects 14.2.11. Exceptions 14.3. netrc — netrc file processing 14.3.1. netrc Objects 14.4. xdrlib — Encode and decode XDR data 14.4.1. Packer Objects 14.4.2. Unpacker Objects 14.4.3. Exceptions 14.5. plistlib — Generate and parse Mac OS X .plist files 14.5.1. Examples 15. Cryptographic Services 15.1. hashlib — Secure hashes and message digests 15.1.1. Hash algorithms 15.1.2. SHAKE variable length digests 15.1.3. Key derivation 15.1.4. BLAKE2 15.1.4.1. Creating hash objects 15.1.4.2. Constants 15.1.4.3. Examples 15.1.4.3.1. Simple hashing 15.1.4.3.2. Using different digest sizes 15.1.4.3.3. Keyed hashing 15.1.4.3.4. Randomized hashing 15.1.4.3.5. Personalization 15.1.4.3.6. Tree mode 15.1.4.4. Credits 15.2. hmac — Keyed-Hashing for Message Authentication 15.3. secrets — Generate secure random numbers for managing secrets 15.3.1. Random numbers 15.3.2. Generating tokens 15.3.2.1. How many bytes should tokens use? 15.3.3. Other functions 15.3.4. Recipes and best practices 16. Generic Operating System Services 16.1. os — Miscellaneous operating system interfaces 16.1.1. File Names, Command Line Arguments, and Environment Variables 16.1.2. Process Parameters 16.1.3. File Object Creation 16.1.4. File Descriptor Operations 16.1.4.1. Querying the size of a terminal 16.1.4.2. Inheritance of File Descriptors 16.1.5. Files and Directories 16.1.5.1. Linux extended attributes 16.1.6. Process Management 16.1.7. Interface to the scheduler 16.1.8. Miscellaneous System Information 16.1.9. Random numbers 16.2. io — Core tools for working with streams 16.2.1. Overview 16.2.1.1. Text I/O 16.2.1.2. Binary I/O 16.2.1.3. Raw I/O 16.2.2. High-level Module Interface 16.2.2.1. In-memory streams 16.2.3. Class hierarchy 16.2.3.1. I/O Base Classes 16.2.3.2. Raw File I/O 16.2.3.3. Buffered Streams 16.2.3.4. Text I/O 16.2.4. Performance 16.2.4.1. Binary I/O 16.2.4.2. Text I/O 16.2.4.3. Multi-threading 16.2.4.4. Reentrancy 16.3. time — Time access and conversions 16.3.1. Functions 16.3.2. Clock ID Constants 16.3.3. Timezone Constants 16.4. argparse — Parser for command-line options, arguments and sub-commands 16.4.1. Example 16.4.1.1. Creating a parser 16.4.1.2. Adding arguments 16.4.1.3. Parsing arguments 16.4.2. ArgumentParser objects 16.4.2.1. prog 16.4.2.2. usage 16.4.2.3. description 16.4.2.4. epilog 16.4.2.5. parents 16.4.2.6. formatter_class 16.4.2.7. prefix_chars 16.4.2.8. fromfile_prefix_chars 16.4.2.9. argument_default 16.4.2.10. allow_abbrev 16.4.2.11. conflict_handler 16.4.2.12. add_help 16.4.3. The add_argument() method 16.4.3.1. name or flags 16.4.3.2. action 16.4.3.3. nargs 16.4.3.4. const 16.4.3.5. default 16.4.3.6. type 16.4.3.7. choices 16.4.3.8. required 16.4.3.9. help 16.4.3.10. metavar 16.4.3.11. dest 16.4.3.12. Action classes 16.4.4. The parse_args() method 16.4.4.1. Option value syntax 16.4.4.2. Invalid arguments 16.4.4.3. Arguments containing - 16.4.4.4. Argument abbreviations (prefix matching) 16.4.4.5. Beyond sys.argv 16.4.4.6. The Namespace object 16.4.5. Other utilities 16.4.5.1. Sub-commands 16.4.5.2. FileType objects 16.4.5.3. Argument groups 16.4.5.4. Mutual exclusion 16.4.5.5. Parser defaults 16.4.5.6. Printing help 16.4.5.7. Partial parsing 16.4.5.8. Customizing file parsing 16.4.5.9. Exiting methods 16.4.6. Upgrading optparse code 16.5. getopt — C-style parser for command line options 16.6. logging — Logging facility for Python 16.6.1. Logger Objects 16.6.2. Logging Levels 16.6.3. Handler Objects 16.6.4. Formatter Objects 16.6.5. Filter Objects 16.6.6. LogRecord Objects 16.6.7. LogRecord attributes 16.6.8. LoggerAdapter Objects 16.6.9. Thread Safety 16.6.10. Module-Level Functions 16.6.11. Module-Level Attributes 16.6.12. Integration with the warnings module 16.7. logging.config — Logging configuration 16.7.1. Configuration functions 16.7.2. Configuration dictionary schema 16.7.2.1. Dictionary Schema Details 16.7.2.2. Incremental Configuration 16.7.2.3. Object connections 16.7.2.4. User-defined objects 16.7.2.5. Access to external objects 16.7.2.6. Access to internal objects 16.7.2.7. Import resolution and custom importers 16.7.3. Configuration file format 16.8. logging.handlers — Logging handlers 16.8.1. StreamHandler 16.8.2. FileHandler 16.8.3. NullHandler 16.8.4. WatchedFileHandler 16.8.5. BaseRotatingHandler 16.8.6. RotatingFileHandler 16.8.7. TimedRotatingFileHandler 16.8.8. SocketHandler 16.8.9. DatagramHandler 16.8.10. SysLogHandler 16.8.11. NTEventLogHandler 16.8.12. SMTPHandler 16.8.13. MemoryHandler 16.8.14. HTTPHandler 16.8.15. QueueHandler 16.8.16. QueueListener 16.9. getpass — Portable password input 16.10. curses — Terminal handling for character-cell displays 16.10.1. Functions 16.10.2. Window Objects 16.10.3. Constants 16.11. curses.textpad — Text input widget for curses programs 16.11.1. Textbox objects 16.12. curses.ascii — Utilities for ASCII characters 16.13. curses.panel — A panel stack extension for curses 16.13.1. Functions 16.13.2. Panel Objects 16.14. platform — Access to underlying platform’s identifying data 16.14.1. Cross Platform 16.14.2. Java Platform 16.14.3. Windows Platform 16.14.3.1. Win95/98 specific 16.14.4. Mac OS Platform 16.14.5. Unix Platforms 16.15. errno — Standard errno system symbols 16.16. ctypes — A foreign function library for Python 16.16.1. ctypes tutorial 16.16.1.1. Loading dynamic link libraries 16.16.1.2. Accessing functions from loaded dlls 16.16.1.3. Calling functions 16.16.1.4. Fundamental data types 16.16.1.5. Calling functions, continued 16.16.1.6. Calling functions with your own custom data types 16.16.1.7. Specifying the required argument types (function prototypes) 16.16.1.8. Return types 16.16.1.9. Passing pointers (or: passing parameters by reference) 16.16.1.10. Structures and unions 16.16.1.11. Structure/union alignment and byte order 16.16.1.12. Bit fields in structures and unions 16.16.1.13. Arrays 16.16.1.14. Pointers 16.16.1.15. Type conversions 16.16.1.16. Incomplete Types 16.16.1.17. Callback functions 16.16.1.18. Accessing values exported from dlls 16.16.1.19. Surprises 16.16.1.20. Variable-sized data types 16.16.2. ctypes reference 16.16.2.1. Finding shared libraries 16.16.2.2. Loading shared libraries 16.16.2.3. Foreign functions 16.16.2.4. Function prototypes 16.16.2.5. Utility functions 16.16.2.6. Data types 16.16.2.7. Fundamental data types 16.16.2.8. Structured data types 16.16.2.9. Arrays and pointers 17. Concurrent Execution 17.1. threading — Thread-based parallelism 17.1.1. Thread-Local Data 17.1.2. Thread Objects 17.1.3. Lock Objects 17.1.4. RLock Objects 17.1.5. Condition Objects 17.1.6. Semaphore Objects 17.1.6.1. Semaphore Example 17.1.7. Event Objects 17.1.8. Timer Objects 17.1.9. Barrier Objects 17.1.10. Using locks, conditions, and semaphores in the with statement 17.2. multiprocessing — Process-based parallelism 17.2.1. Introduction 17.2.1.1. The Process class 17.2.1.2. Contexts and start methods 17.2.1.3. Exchanging objects between processes 17.2.1.4. Synchronization between processes 17.2.1.5. Sharing state between processes 17.2.1.6. Using a pool of workers 17.2.2. Reference 17.2.2.1. Process and exceptions 17.2.2.2. Pipes and Queues 17.2.2.3. Miscellaneous 17.2.2.4. Connection Objects 17.2.2.5. Synchronization primitives 17.2.2.6. Shared ctypes Objects 17.2.2.6.1. The multiprocessing.sharedctypes module 17.2.2.7. Managers 17.2.2.7.1. Customized managers 17.2.2.7.2. Using a remote manager 17.2.2.8. Proxy Objects 17.2.2.8.1. Cleanup 17.2.2.9. Process Pools 17.2.2.10. Listeners and Clients 17.2.2.10.1. Address Formats 17.2.2.11. Authentication keys 17.2.2.12. Logging 17.2.2.13. The multiprocessing.dummy module 17.2.3. Programming guidelines 17.2.3.1. All start methods 17.2.3.2. The spawn and forkserver start methods 17.2.4. Examples 17.3. The concurrent package 17.4. concurrent.futures — Launching parallel tasks 17.4.1. Executor Objects 17.4.2. ThreadPoolExecutor 17.4.2.1. ThreadPoolExecutor Example 17.4.3. ProcessPoolExecutor 17.4.3.1. ProcessPoolExecutor Example 17.4.4. Future Objects 17.4.5. Module Functions 17.4.6. Exception classes 17.5. subprocess — Subprocess management 17.5.1. Using the subprocess Module 17.5.1.1. Frequently Used Arguments 17.5.1.2. Popen Constructor 17.5.1.3. Exceptions 17.5.2. Security Considerations 17.5.3. Popen Objects 17.5.4. Windows Popen Helpers 17.5.4.1. Constants 17.5.5. Older high-level API 17.5.6. Replacing Older Functions with the subprocess Module 17.5.6.1. Replacing /bin/sh shell backquote 17.5.6.2. Replacing shell pipeline 17.5.6.3. Replacing os.system() 17.5.6.4. Replacing the os.spawn family 17.5.6.5. Replacing os.popen(), os.popen2(), os.popen3() 17.5.6.6. Replacing functions from the popen2 module 17.5.7. Legacy Shell Invocation Functions 17.5.8. Notes 17.5.8.1. Converting an argument sequence to a string on Windows 17.6. sched — Event scheduler 17.6.1. Scheduler Objects 17.7. queue — A synchronized queue class 17.7.1. Queue Objects 17.8. dummy_threading — Drop-in replacement for the threading module 17.9. _thread — Low-level threading API 17.10. _dummy_thread — Drop-in replacement for the _thread module 18. Interprocess Communication and Networking 18.1. socket — Low-level networking interface 18.1.1. Socket families 18.1.2. Module contents 18.1.2.1. Exceptions 18.1.2.2. Constants 18.1.2.3. Functions 18.1.2.3.1. Creating sockets 18.1.2.3.2. Other functions 18.1.3. Socket Objects 18.1.4. Notes on socket timeouts 18.1.4.1. Timeouts and the connect method 18.1.4.2. Timeouts and the accept method 18.1.5. Example 18.2. ssl — TLS/SSL wrapper for socket objects 18.2.1. Functions, Constants, and Exceptions 18.2.1.1. Socket creation 18.2.1.2. Context creation 18.2.1.3. 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Event loop policy interface 18.5.2.6. Access to the global loop policy 18.5.2.7. Customizing the event loop policy 18.5.3. Tasks and coroutines 18.5.3.1. Coroutines 18.5.3.1.1. Example: Hello World coroutine 18.5.3.1.2. Example: Coroutine displaying the current date 18.5.3.1.3. Example: Chain coroutines 18.5.3.2. InvalidStateError 18.5.3.3. TimeoutError 18.5.3.4. Future 18.5.3.4.1. Example: Future with run_until_complete() 18.5.3.4.2. Example: Future with run_forever() 18.5.3.5. Task 18.5.3.5.1. Example: Parallel execution of tasks 18.5.3.6. Task functions 18.5.4. Transports and protocols (callback based API) 18.5.4.1. Transports 18.5.4.1.1. BaseTransport 18.5.4.1.2. ReadTransport 18.5.4.1.3. WriteTransport 18.5.4.1.4. DatagramTransport 18.5.4.1.5. BaseSubprocessTransport 18.5.4.2. Protocols 18.5.4.2.1. Protocol classes 18.5.4.2.2. Connection callbacks 18.5.4.2.3. Streaming protocols 18.5.4.2.4. Datagram protocols 18.5.4.2.5. Flow control callbacks 18.5.4.2.6. Coroutines and protocols 18.5.4.3. Protocol examples 18.5.4.3.1. TCP echo client protocol 18.5.4.3.2. TCP echo server protocol 18.5.4.3.3. UDP echo client protocol 18.5.4.3.4. UDP echo server protocol 18.5.4.3.5. Register an open socket to wait for data using a protocol 18.5.5. Streams (coroutine based API) 18.5.5.1. Stream functions 18.5.5.2. StreamReader 18.5.5.3. StreamWriter 18.5.5.4. StreamReaderProtocol 18.5.5.5. IncompleteReadError 18.5.5.6. LimitOverrunError 18.5.5.7. Stream examples 18.5.5.7.1. TCP echo client using streams 18.5.5.7.2. TCP echo server using streams 18.5.5.7.3. Get HTTP headers 18.5.5.7.4. Register an open socket to wait for data using streams 18.5.6. Subprocess 18.5.6.1. Windows event loop 18.5.6.2. Create a subprocess: high-level API using Process 18.5.6.3. Create a subprocess: low-level API using subprocess.Popen 18.5.6.4. Constants 18.5.6.5. Process 18.5.6.6. Subprocess and threads 18.5.6.7. Subprocess examples 18.5.6.7.1. 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NamedNodeMap Objects 20.6.2.9. Comment Objects 20.6.2.10. Text and CDATASection Objects 20.6.2.11. ProcessingInstruction Objects 20.6.2.12. Exceptions 20.6.3. Conformance 20.6.3.1. Type Mapping 20.6.3.2. Accessor Methods 20.7. xml.dom.minidom — Minimal DOM implementation 20.7.1. DOM Objects 20.7.2. DOM Example 20.7.3. minidom and the DOM standard 20.8. xml.dom.pulldom — Support for building partial DOM trees 20.8.1. DOMEventStream Objects 20.9. xml.sax — Support for SAX2 parsers 20.9.1. SAXException Objects 20.10. xml.sax.handler — Base classes for SAX handlers 20.10.1. ContentHandler Objects 20.10.2. DTDHandler Objects 20.10.3. EntityResolver Objects 20.10.4. ErrorHandler Objects 20.11. xml.sax.saxutils — SAX Utilities 20.12. xml.sax.xmlreader — Interface for XML parsers 20.12.1. XMLReader Objects 20.12.2. IncrementalParser Objects 20.12.3. Locator Objects 20.12.4. InputSource Objects 20.12.5. The Attributes Interface 20.12.6. The AttributesNS Interface 20.13. xml.parsers.expat — Fast XML parsing using Expat 20.13.1. XMLParser Objects 20.13.2. ExpatError Exceptions 20.13.3. Example 20.13.4. Content Model Descriptions 20.13.5. Expat error constants 21. Internet Protocols and Support 21.1. webbrowser — Convenient Web-browser controller 21.1.1. Browser Controller Objects 21.2. cgi — Common Gateway Interface support 21.2.1. Introduction 21.2.2. Using the cgi module 21.2.3. Higher Level Interface 21.2.4. Functions 21.2.5. Caring about security 21.2.6. Installing your CGI script on a Unix system 21.2.7. Testing your CGI script 21.2.8. Debugging CGI scripts 21.2.9. Common problems and solutions 21.3. cgitb — Traceback manager for CGI scripts 21.4. wsgiref — WSGI Utilities and Reference Implementation 21.4.1. wsgiref.util – WSGI environment utilities 21.4.2. wsgiref.headers – WSGI response header tools 21.4.3. wsgiref.simple_server – a simple WSGI HTTP server 21.4.4. wsgiref.validate — WSGI conformance checker 21.4.5. wsgiref.handlers – server/gateway base classes 21.4.6. Examples 21.5. urllib — URL handling modules 21.6. urllib.request — Extensible library for opening URLs 21.6.1. Request Objects 21.6.2. OpenerDirector Objects 21.6.3. BaseHandler Objects 21.6.4. HTTPRedirectHandler Objects 21.6.5. HTTPCookieProcessor Objects 21.6.6. ProxyHandler Objects 21.6.7. HTTPPasswordMgr Objects 21.6.8. HTTPPasswordMgrWithPriorAuth Objects 21.6.9. AbstractBasicAuthHandler Objects 21.6.10. HTTPBasicAuthHandler Objects 21.6.11. ProxyBasicAuthHandler Objects 21.6.12. AbstractDigestAuthHandler Objects 21.6.13. HTTPDigestAuthHandler Objects 21.6.14. ProxyDigestAuthHandler Objects 21.6.15. HTTPHandler Objects 21.6.16. HTTPSHandler Objects 21.6.17. FileHandler Objects 21.6.18. DataHandler Objects 21.6.19. FTPHandler Objects 21.6.20. CacheFTPHandler Objects 21.6.21. UnknownHandler Objects 21.6.22. HTTPErrorProcessor Objects 21.6.23. Examples 21.6.24. Legacy interface 21.6.25. urllib.request Restrictions 21.7. urllib.response — Response classes used by urllib 21.8. urllib.parse — Parse URLs into components 21.8.1. URL Parsing 21.8.2. Parsing ASCII Encoded Bytes 21.8.3. Structured Parse Results 21.8.4. URL Quoting 21.9. urllib.error — Exception classes raised by urllib.request 21.10. urllib.robotparser — Parser for robots.txt 21.11. http — HTTP modules 21.11.1. HTTP status codes 21.12. http.client — HTTP protocol client 21.12.1. HTTPConnection Objects 21.12.2. HTTPResponse Objects 21.12.3. Examples 21.12.4. HTTPMessage Objects 21.13. ftplib — FTP protocol client 21.13.1. FTP Objects 21.13.2. FTP_TLS Objects 21.14. poplib — POP3 protocol client 21.14.1. POP3 Objects 21.14.2. POP3 Example 21.15. imaplib — IMAP4 protocol client 21.15.1. IMAP4 Objects 21.15.2. IMAP4 Example 21.16. nntplib — NNTP protocol client 21.16.1. NNTP Objects 21.16.1.1. Attributes 21.16.1.2. Methods 21.16.2. Utility functions 21.17. smtplib — SMTP protocol client 21.17.1. SMTP Objects 21.17.2. SMTP Example 21.18. smtpd — SMTP Server 21.18.1. SMTPServer Objects 21.18.2. DebuggingServer Objects 21.18.3. PureProxy Objects 21.18.4. MailmanProxy Objects 21.18.5. SMTPChannel Objects 21.19. telnetlib — Telnet client 21.19.1. Telnet Objects 21.19.2. Telnet Example 21.20. uuid — UUID objects according to RFC 4122 21.20.1. Example 21.21. socketserver — A framework for network servers 21.21.1. Server Creation Notes 21.21.2. Server Objects 21.21.3. Request Handler Objects 21.21.4. Examples 21.21.4.1. socketserver.TCPServer Example 21.21.4.2. socketserver.UDPServer Example 21.21.4.3. Asynchronous Mixins 21.22. http.server — HTTP servers 21.23. http.cookies — HTTP state management 21.23.1. Cookie Objects 21.23.2. Morsel Objects 21.23.3. Example 21.24. http.cookiejar — Cookie handling for HTTP clients 21.24.1. CookieJar and FileCookieJar Objects 21.24.2. FileCookieJar subclasses and co-operation with web browsers 21.24.3. CookiePolicy Objects 21.24.4. DefaultCookiePolicy Objects 21.24.5. Cookie Objec

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内容概要：本文《IntelliJ IDEA安装与环境配置指南》系统介绍了2026年最新版IntelliJ IDEA在Windows、macOS和Linux三大平台下的全流程安装与环境搭建方法。内容涵盖版本选择（社区版与旗舰版对比）、系统硬件要求、各操作系统具体安装步骤、初始界面配置、Maven与Gradle构建工具集成，以及常见问题的解决方案。文中强调了正确配置JDK、构建工具路径、文件编码等关键环节，并提供了提升开发效率的实用建议，如使用JetBrains Toolbox管理IDE、配置阿里云Maven镜像加速依赖下载等。; 适合人群：Java初学者、从事后端或全栈开发的程序员、需要在多平台上部署开发环境的工程师；尤其适合刚接触IntelliJ IDEA或希望优化现有配置的研发人员。; 使用场景及目标：①为新机器快速搭建稳定高效的Java开发环境；②解决因环境配置不当导致的项目构建失败、依赖下载缓慢、中文乱码等问题；③掌握IDEA与主流构建工具（Maven/Gradle）的深度集成技巧，提升团队协作一致性与开发效率。; 阅读建议：建议读者结合自身操作系统按步骤操作，重点关注版本匹配、路径规范性和编码统一性；实操过程中可配合文中的命令示例与配置片段进行验证，遇到问题时参考“常见问题”章节定位解决。

LAT1650STM32H7系列ADC-DMA传输异常案例分析-v1.0

内容概要：本文通过一个实际案例分析了STM32H7系列芯片在使用ADC配合DMA传输数据时可能出现的异常问题。详细探讨了配置错误（如误选BDMA而非DMA1/2）、内存区域访问限制（如TCM不可被DMA访问）、以及DCache导致的数据不一致等问题，并给出了相应的解决方案，包括正确选择DMA控制器、合理分配缓冲区内存位置及进行Cache一致性维护操作。最终通过禁用Cache或在DMA中断中执行Cache维护操作解决了数据显示异常问题。; 适合人群：嵌入式系统开发工程师，尤其是熟悉STM32系列微控制器并有一定硬件调试经验的中高级研发人员。; 使用场景及目标：①解决STM32H7系列MCU中ADC与DMA协同工作时的数据传输故障；②理解Cache机制对实时数据采集的影响并掌握MPU配置与Cache管理方法；③提升对STM32系统架构、总线互联和内存映射的深入认识；阅读建议：此文档侧重于实战问题排查，建议结合STM32CubeMX工具、KEIL调试环境和参考手册同步实践，重点关注DMA配置、内存布局与Cache管理之间的关联性，在真实项目中注意规避类似陷阱。

三自由度汽车操纵侧翻模型仿真【侧向侧倾横摆】

内容概要：本文档详细介绍了一套三自由度汽车操纵侧翻模型的Simulink仿真资源，涵盖车辆在侧向、侧倾与横摆三个自由度下的动力学建模过程，提供了完整的数学建模公式、系统参数设置及仿真模型架构。该模型能够有效模拟车辆在复杂行驶工况下的动态响应，尤其适用于分析高速转向、紧急避障等场景下的侧翻稳定性问题，为车辆安全性评估与主动安全控制系统设计提供理论支撑。此外，文档还系统整理了大量MATLAB/Simulink仿真资源，覆盖电力系统、智能优化算法、机器学习、路径规划、信号处理、新能源系统、机器人控制等多个前沿科研方向，构成一个跨学科、综合性的科研资源共享平台。; 适合人群：面向具备车辆动力学、控制理论或机械电子工程背景的研究生、科研人员及工程技术人员，尤其适合从事汽车安全控制、动力学仿真与稳定性分析的相关从业者；同时也适用于正在开展MATLAB/Simulink仿真实验的初级至中级科研人员。; 使用场景及目标：①构建并仿真三自由度汽车操纵动力学模型，深入分析车辆侧倾与横摆耦合运动对操控稳定性的影响；②结合实测或标准参数完成系统仿真，支持车辆电子稳定程序（ESP）、主动悬架等安全控制策略的设计与验证；③作为多领域科研资源包的重要组成部分，服务于智能算法优化、新能源系统建模、微电网调度、路径规划等交叉学科研究，提升科研效率与创新能力。; 阅读建议：建议使用者结合文档中提供的详细公式与参数，在Simulink环境中逐步搭建并调试模型，注重理论推导与仿真实践的深度融合；对于其他相关仿真资源，可根据具体研究方向选择性下载与学习，充分利用共享资料拓展技术视野，推动科研工作的系统化与创新化发展。

自由度汽车操纵Simulink模型（侧向、侧倾、横摆-带数据参数与详细公式文档）

内容概要：本文档提供了基于Simulink的汽车操纵动力学仿真模型，涵盖车辆侧向、侧倾与横摆三自由度的动态建模，包含详细的运动方程、系统参数设置及仿真结构图。该模型基于经典车辆动力学理论，构建了高精度的多自由度耦合系统，能够准确反映车辆在复杂工况下的操纵稳定性和动态响应特性。文档详细阐述了各子系统的数学建模过程，包括轮胎力学模型（如魔术公式或线性简化模型）、悬挂系统动力学、质心运动学关系及外部力矩平衡方程，并提供了完整的Simulink模块搭建方案，支持用户进行模型验证、参数敏感性分析与控制算法开发。该模型可广泛应用于车辆稳定性控制系统（如ESP、AFS）的设计与测试，也可作为高级驾驶辅助系统（ADAS）和自动驾驶算法开发中的车辆仿真平台，具备良好的可扩展性与二次开发潜力。; 适合人群：面向车辆工程、自动化、机械电子等相关专业的研究生、科研人员及从事汽车动力学与控制系统的研发工程师；要求使用者具备一定的Matlab/Simulink操作能力、系统建模基础以及车辆动力学相关理论知识。; 使用场景及目标：①用于高校教学与科研中对车辆多自由度运动行为的建模与仿真分析，加深对操纵稳定性机理的理解；②支撑车辆稳定性控制系统（如电子稳定程序ESP、主动前轮转向AFS）的设计与控制策略验证；③作为自动驾驶系统中车辆模型仿真的核心模块，为路径跟踪、轨迹规划与控制算法提供高保真动力学支撑，提升整体系统的可靠性与实际控制效果。; 阅读建议：建议结合经典车辆动力学教材（如《Vehicle Dynamics and Control》）同步学习，重点理解三自由度模型中侧向、侧倾与横摆运动的耦合机制、坐标系定义及轮胎力建模方法；在实际应用中应根据具体车型参数（质量、转动惯量、悬挂刚度等）对模型进行校准，并通过阶跃转向、双移线等标准工况仿真不断调试与验证模型响应特性，确保其在不同速度和路面条件下的准确性与鲁棒性。

光储充+三相并网交直流系统（一）（带电池负载）基于Matlabsimulink光储充交直流并网仿真（光伏储能充电桩交直流系统）可孤岛运行可并网运行（Simulink仿真实现）

内容概要：本文档详细介绍了基于Matlab/Simulink平台构建的光储充一体化三相交直流并网仿真系统，涵盖光伏发电、储能系统与充电桩的集成建模，支持并网与孤岛两种运行模式。系统实现了能量管理策略、电池荷电状态（SOC）控制、并网逆变器控制（如VSG、MPPT）、功率协调调度等核心技术模块，重点展示了微电网在不同工况下的动态响应特性与稳定性表现。文档不仅提供了完整的Simulink仿真模型，还配套丰富的算法代码、控制逻辑说明及论文复现资料，涵盖从底层器件建模到上层优化调度的多层次研究内容，突出了其在新能源电力系统仿真与创新研究中的综合应用价值。; 适合人群：面向具备电力电子、自动化、新能源系统等相关背景的研究生、科研人员及工程技术人员，尤其适用于从事微电网控制、储能系统集成、分布式能源并网技术、能量管理系统（EMS）开发等方向的研究与实践工作者。; 使用场景及目标：①开展光伏-储能-充电桩一体化系统的建模与仿真分析；②研究微电网在并网与孤岛模式间的无缝切换控制策略；③验证能量管理算法（如多目标优化、分层控制）、逆变器控制技术（如虚拟同步机VSG、锁相环PLL）的有效性；④支撑科研项目、学位论文撰写或工程原型开发，提升对新型电力系统运行机制的理解与设计能力。; 其他说明：所有资源可通过指定公众号“荔枝科研社”及百度网盘链接免费获取，包含Simulink模型文件、Matlab代码、Python脚本、实验数据与完整论文文档。文档倡导“借力科研”理念，鼓励结合成熟工具与自主创新，系统性推进科研进程，适合作为科研入门与项目实践的重要参考资料。

光储(光伏储能)虚拟同步VSG并网有功无功跟随（Simulink仿真实现）

内容概要：本文档聚焦于“光储(光伏储能)虚拟同步VSG并网有功无功跟随（Simulink仿真实现）”的技术研究，系统阐述了基于Simulink平台构建光伏储能系统并网运行的虚拟同步发电机（VSG）控制策略，旨在实现有功功率与无功功率的精确动态跟踪。文档深入解析了VSG的核心原理及其数学模型，重点探讨其在模拟传统同步电机惯性与阻尼特性方面的机制，从而有效提升新能源并网系统的频率与电压稳定性。通过建立完整的系统仿真模型，详细展示了从光伏发电、储能单元到并网逆变器的整体架构，并对VSG的有功-频率下垂控制、无功-电压下垂控制等关键算法进行设计与验证。研究内容涵盖了系统建模、控制逻辑实现、动态响应仿真及并网性能评估，充分论证了VSG技术在改善电能质量、增强电网适应能力和支撑弱电网运行方面的显著优势。; 适合人群：适用于具备电力系统分析、电力电子技术及自动控制理论基础，熟悉Matlab/Simulink仿真环境的科研人员、研究生以及从事新能源发电、微电网控制、储能系统集成和智能电网技术研发的工程技术人员。; 使用场景及目标：① 深入掌握光伏储能系统接入大电网的虚拟同步控制核心技术；② 学习并实践VSG的有功与无功功率协同控制策略的设计与实现方法；③ 利用Simulink进行电力系统电磁暂态仿真，分析系统在负载突变、电网波动等工况下的动态响应与稳定性；④ 为相关领域的学术研究、工程项目开发、技术方案论证及学位论文撰写提供可靠的仿真模型与技术参考。; 阅读建议：建议读者结合电力系统稳定性和现代控制理论的相关知识，循序渐进地理解VSG的控制思想，在Simulink环境中动手复现仿真模型，通过调整控制器参数（如虚拟惯量、阻尼系数）来观察系统动态性能的变化，从而深刻领会VSG技术在提升新能源并网友好性方面的作用机理。

终于实现微电网点对点交易！多微网点对点分布式电能交易策略程序代码！（Matlab代码实现）

内容概要：本文档提供了基于Matlab实现的多微电网点对点分布式电能交易策略程序代码，旨在推动微电网之间高效、灵活的能源交互。资源聚焦于分布式能源系统中的电能交易机制，涵盖交易策略的设计、优化算法的应用及仿真验证全过程，结合智能优化与电力系统建模技术，解决多微网环境下的能源分配、交易效率、系统稳定性与经济性等关键问题。同时，文档还列举了大量相关科研方向的Matlab/Simulink仿真资源，覆盖微电网优化、储能配置、电力市场交易、可再生能源预测、综合能源系统调度等多个前沿领域，突出其在高水平论文复现与科研创新中的实用价值。; 适合人群：具备电力系统、能源互联网、自动化或相关专业背景，熟悉Matlab/Simulink仿真环境，正在从事新能源、微电网、电力市场等领域研究的研究生、高校教师及工程技术人员。; 使用场景及目标：①开展多微电网点对点电能交易机制的研究与建模仿真；②复现或改进顶刊论文中的分布式优化与市场交易算法；③支撑科研课题、学位论文撰写及科研项目申报中的仿真验证工作；阅读建议：建议结合文中提供的网盘资料与公众号资源，系统性查阅配套代码与说明文档，优先掌握核心算法实现流程，并根据具体研究需求进行参数调整与模型拓展，以提升科研效率与技术创新能力。

基于多时段动态电价的电动汽车有序充电策略优化（Matlab代码实现）

内容概要：本文围绕“基于多时段动态电价的电动汽车有序充电策略优化”展开，利用Matlab代码实现相关算法与仿真，旨在通过动态电价机制引导电动汽车用户在电网负荷低谷时段充电，从而实现削峰填谷、降低电网压力、提升能源利用效率的目标。研究构建了综合考虑电价波动、用户充电需求及电网承载能力的多目标优化模型，并采用粒子群、遗传算法等智能优化算法对电动汽车充电行为进行建模与求解，通过仿真实验验证了该策略在改善负荷曲线、减少用户充电成本方面的有效性与可行性，为车网互动（V2G）和需求侧管理提供了理论支持与技术路径。; 适合人群：具备一定电力系统、智能优化算法或Matlab编程基础的科研人员、研究生及工程技术人员，尤其适用于从事新能源汽车、智慧能源系统、需求响应、电力市场等领域研究的专业人士。; 使用场景及目标：①应用于智能电网中电动汽车有序充电管理系统的设计与优化；②服务于电力公司制定分时电价政策与实施需求响应策略；③作为学术研究中关于车网互动（V2G）、负荷调度、多目标优化算法验证的技术支撑。; 阅读建议：此资源以Matlab代码为核心，建议读者结合文档内容与代码实现同步学习，重点关注多时段电价建模、目标函数设计及优化算法实现细节，宜在实际仿真环境中调试运行，深入理解参数设置对优化结果的影响。

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