Python Documentation contents
- What’s New in Python
- What’s New In Python 3.8
- Summary – Release highlights
- New Features
- Assignment expressions
- Positional-only parameters
- Parallel filesystem cache for compiled bytecode files
- Debug build uses the same ABI as release build
- f-strings support
=for self-documenting expressions and debugging - PEP 578: Python Runtime Audit Hooks
- PEP 587: Python Initialization Configuration
- Vectorcall: a fast calling protocol for CPython
- Pickle protocol 5 with out-of-band data buffers
- Other Language Changes
- New Modules
- Improved Modules
- ast
- asyncio
- builtins
- collections
- cProfile
- csv
- curses
- ctypes
- datetime
- functools
- gc
- gettext
- gzip
- IDLE and idlelib
- inspect
- io
- itertools
- json.tool
- logging
- math
- mmap
- multiprocessing
- os
- os.path
- pathlib
- pickle
- plistlib
- pprint
- py_compile
- shlex
- shutil
- socket
- ssl
- statistics
- sys
- tarfile
- threading
- tokenize
- tkinter
- time
- typing
- unicodedata
- unittest
- venv
- weakref
- xml
- xmlrpc
- Optimizations
- Build and C API Changes
- Deprecated
- API and Feature Removals
- Porting to Python 3.8
- Notable changes in Python 3.8.1
- Notable changes in Python 3.8.2
- Notable changes in Python 3.8.3
- What’s New In Python 3.7
- Summary – Release Highlights
- New Features
- PEP 563: Postponed Evaluation of Annotations
- PEP 538: Legacy C Locale Coercion
- PEP 540: Forced UTF-8 Runtime Mode
- PEP 553: Built-in
breakpoint() - PEP 539: New C API for Thread-Local Storage
- PEP 562: Customization of Access to Module Attributes
- PEP 564: New Time Functions With Nanosecond Resolution
- PEP 565: Show DeprecationWarning in
__main__ - PEP 560: Core Support for
typingmodule and Generic Types - PEP 552: Hash-based .pyc Files
- PEP 545: Python Documentation Translations
- Development Runtime Mode: -X dev
- Other Language Changes
- New Modules
- Improved Modules
- argparse
- asyncio
- binascii
- calendar
- collections
- compileall
- concurrent.futures
- contextlib
- cProfile
- crypt
- datetime
- dbm
- decimal
- dis
- distutils
- enum
- functools
- gc
- hmac
- http.client
- http.server
- idlelib and IDLE
- importlib
- io
- ipaddress
- itertools
- locale
- logging
- math
- mimetypes
- msilib
- multiprocessing
- os
- pathlib
- pdb
- py_compile
- pydoc
- queue
- re
- signal
- socket
- socketserver
- sqlite3
- ssl
- string
- subprocess
- sys
- time
- tkinter
- tracemalloc
- types
- unicodedata
- unittest
- unittest.mock
- urllib.parse
- uu
- uuid
- warnings
- xml.etree
- xmlrpc.server
- zipapp
- zipfile
- C API Changes
- Build Changes
- Optimizations
- Other CPython Implementation Changes
- Deprecated Python Behavior
- Deprecated Python modules, functions and methods
- Deprecated functions and types of the C API
- Platform Support Removals
- API and Feature Removals
- Module Removals
- Windows-only Changes
- Porting to Python 3.7
- Notable changes in Python 3.7.1
- Notable changes in Python 3.7.2
- Notable changes in Python 3.7.6
- 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
- Improved Modules
- array
- ast
- asyncio
- binascii
- cmath
- collections
- concurrent.futures
- contextlib
- datetime
- decimal
- distutils
- 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
- Removed
- Porting to Python 3.6
- Notable changes in Python 3.6.2
- Notable changes in Python 3.6.4
- Notable changes in Python 3.6.5
- Notable changes in Python 3.6.7
- Notable changes in Python 3.6.10
- 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
- Improved Modules
- argparse
- asyncio
- bz2
- cgi
- cmath
- code
- collections
- collections.abc
- compileall
- concurrent.futures
- configparser
- contextlib
- csv
- curses
- dbm
- difflib
- distutils
- doctest
- 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
- 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
- Removed
- Porting to Python 3.5
- Notable changes in Python 3.5.4
- What’s New In Python 3.4
- Summary – Release Highlights
- New Features
- New Modules
- Improved Modules
- abc
- aifc
- argparse
- audioop
- base64
- collections
- colorsys
- contextlib
- dbm
- dis
- doctest
- 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
- Deprecated
- Removed
- Porting to Python 3.4
- Changed in 3.4.3
- 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
- PEP 393: Flexible String Representation
- 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
- Using importlib as the Implementation of Import
- Other Language Changes
- A Finer-Grained Import Lock
- Builtin functions and types
- New Modules
- Improved Modules
- abc
- array
- base64
- binascii
- bz2
- codecs
- collections
- contextlib
- crypt
- curses
- datetime
- decimal
- 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
- Porting to Python 3.3
- 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.futuresmodule - 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
- 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
- What’s New In 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
- New and Improved Modules
- Build and C API Changes
- Other Changes and Fixes
- Porting to Python 2.7
- New Features Added to Python 2.7 Maintenance Releases
- Two new environment variables for debug mode
- PEP 434: IDLE Enhancement Exception for All Branches
- PEP 466: Network Security Enhancements for Python 2.7
- PEP 477: Backport ensurepip (PEP 453) to Python 2.7
- PEP 476: Enabling certificate verification by default for stdlib http clients
- PEP 493: HTTPS verification migration tools for Python 2.7
- New
make regen-allbuild target - Removal of
make touchbuild target
- Acknowledgements
- What’s New in Python 2.6
- Python 3.0
- Changes to the Development Process
- PEP 343: The ‘with’ statement
- PEP 366: Explicit Relative Imports From a Main Module
- PEP 370: Per-user
site-packagesDirectory - PEP 371: The
multiprocessingPackage - PEP 3101: Advanced String Formatting
- PEP 3105:
printAs 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
- Other Language Changes
- New and Improved Modules
- Deprecations and Removals
- Build and C API Changes
- 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
- PEP 352: Exceptions as New-Style Classes
- PEP 353: Using ssize_t as the index type
- PEP 357: The ‘__index__’ method
- Other Language Changes
- New, Improved, and Removed Modules
- Build and C API 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
- PEP 328: Multi-line Imports
- PEP 331: Locale-Independent Float/String Conversions
- Other Language Changes
- New, Improved, and Deprecated Modules
- Build and C API 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
- New, Improved, and Deprecated Modules
- Pymalloc: A Specialized Object Allocator
- Build and C API 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
- 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
- Porting to 2.0
- Extending/Embedding Changes
- Distutils: Making Modules Easy to Install
- XML Modules
- Module changes
- New modules
- IDLE Improvements
- Deleted and Deprecated Modules
- Acknowledgements
- Changelog
- Python next
- Python 3.8.5 final
- Python 3.8.4 final
- Python 3.8.4 release candidate 1
- Python 3.8.3 final
- Python 3.8.3 release candidate 1
- Python 3.8.2 final
- Python 3.8.2 release candidate 2
- Python 3.8.2 release candidate 1
- Python 3.8.1 final
- Python 3.8.1 release candidate 1
- Python 3.8.0 final
- Python 3.8.0 release candidate 1
- Python 3.8.0 beta 4
- Python 3.8.0 beta 3
- Python 3.8.0 beta 2
- Python 3.8.0 beta 1
- Python 3.8.0 alpha 4
- Python 3.8.0 alpha 3
- Python 3.8.0 alpha 2
- Python 3.8.0 alpha 1
- Python 3.7.0 final
- Python 3.7.0 release candidate 1
- Python 3.7.0 beta 5
- Python 3.7.0 beta 4
- Python 3.7.0 beta 3
- Python 3.7.0 beta 2
- Python 3.7.0 beta 1
- Python 3.7.0 alpha 4
- Python 3.7.0 alpha 3
- Python 3.7.0 alpha 2
- Python 3.7.0 alpha 1
- Python 3.6.6 final
- Python 3.6.6 release candidate 1
- Python 3.6.5 final
- Python 3.6.5 release candidate 1
- Python 3.6.4 final
- Python 3.6.4 release candidate 1
- Python 3.6.3 final
- Python 3.6.3 release candidate 1
- Python 3.6.2 final
- Python 3.6.2 release candidate 2
- Python 3.6.2 release candidate 1
- Python 3.6.1 final
- Python 3.6.1 release candidate 1
- Python 3.6.0 final
- Python 3.6.0 release candidate 2
- Python 3.6.0 release candidate 1
- Python 3.6.0 beta 4
- Python 3.6.0 beta 3
- Python 3.6.0 beta 2
- Python 3.6.0 beta 1
- Python 3.6.0 alpha 4
- Python 3.6.0 alpha 3
- Python 3.6.0 alpha 2
- Python 3.6.0 alpha 1
- Python 3.5.5 final
- Python 3.5.5 release candidate 1
- Python 3.5.4 final
- Python 3.5.4 release candidate 1
- Python 3.5.3 final
- Python 3.5.3 release candidate 1
- What’s New In Python 3.8