Python Standard Library (2.7.12)

'''
Python Standard Library

Python 2.7.12 documentation
While The Python Language Reference describes the exact syntax and semantics of the Python language, this library reference manual describes the standard library that is distributed with Python. It also describes some of the optional components that are commonly included in Python distributions.

Python’s standard library is very extensive, offering a wide range of facilities as indicated by the long table of contents listed below. The library contains built-in modules (written in C) that provide access to system functionality such as file I/O that would otherwise be inaccessible to Python programmers, as well as modules written in Python that provide standardized solutions for many problems that occur in everyday programming. Some of these modules are explicitly designed to encourage and enhance the portability of Python programs by abstracting away platform-specifics into platform-neutral APIs.

The Python installers for the Windows platform usually include the entire standard library and often also include many additional components. For Unix-like operating systems Python is normally provided as a collection of packages, so it may be necessary to use the packaging tools provided with the operating system to obtain some or all of the optional components.

In addition to the standard library, there is a growing collection of several thousand components (from individual programs and modules to packages and entire application development frameworks), available from the Python Package Index.


 1.     Introduction
 2.     Built-in Functions
 3.     Non-essential Built-in Functions
 4.     Built-in Constants
                    4.1.    Constants added by the site module
 5.     Built-in Types
                    5.1.    Truth Value Testing
                    5.2.    Boolean Operations -- and, or, not
                    5.3.    Comparisons
                    5.4.    Numeric Types -- int, float, long, complex
                    5.5.    Iterator Types
                    5.6.    Sequence Types -- str, unicode, list, tuple, bytearray, buffer, xrange
                    5.7.    Set Types -- set, frozenset
                    5.8.    Mapping Types -- dict
                    5.9.    File Objects
                    5.10.   memoryview type
                    5.11.   Context Manager Types
                    5.12.   Other Built-in Types
                    5.13.   Special Attributes
 6.     Built-in Exceptions
                    6.1.    Exception hierarchy
 7.     String Services
                    7.1.    string -- Common string operations
                    7.2.    re -- Regular expression operations
                    7.3.    struct -- Interpret strings as packed binary data
                    7.4.    difflib -- Helpers for computing deltas
                    7.5.    StringIO -- Read and write strings as files
                    7.6.    cStringIO -- Faster version of StringIO
                    7.7.    textwrap -- Text wrapping and filling
                    7.8.    codecs -- Codec registry and base classes
                    7.9.    unicodedata -- Unicode Database
                    7.10.   stringprep -- Internet String Preparation
                    7.11.   fpformat -- Floating point conversions
 8.     Data Types
                    8.1.    datetime -- Basic date and time types
                    8.2.    calendar -- General calendar-related functions
                    8.3.    collections -- High-performance container datatypes
                    8.4.    heapq -- Heap queue algorithm
                    8.5.    bisect -- Array bisection algorithm
                    8.6.    array -- Efficient arrays of numeric values
                    8.7.    sets -- Unordered collections of unique elements
                    8.8.    sched -- Event scheduler
                    8.9.    mutex -- Mutual exclusion support
                    8.10.   Queue -- A synchronized queue class
                    8.11.   weakref -- Weak references
                    8.12.   UserDict -- Class wrapper for dictionary objects
                    8.13.   UserList -- Class wrapper for list objects
                    8.14.   UserString -- Class wrapper for string objects
                    8.15.   types -- Names for built-in types
                    8.16.   new -- Creation of runtime internal objects
                    8.17.   copy -- Shallow and deep copy operations
                    8.18.   pprint -- Data pretty printer
                    8.19.   repr -- Alternate repr() implementation
 9.     Numeric and Mathematical Modules
                    9.1.    numbers -- Numeric abstract base classes
                    9.2.    math -- Mathematical functions
                    9.3.    cmath -- Mathematical functions for complex numbers
                    9.4.    decimal -- Decimal fixed point and floating point arithmetic
                    9.5.    fractions -- Rational numbers
                    9.6.    random -- Generate pseudo-random numbers
                    9.7.    itertools -- Functions creating iterators for efficient looping
                    9.8.    functools -- Higher-order functions and operations on callable objects
                    9.9.    operator -- Standard operators as functions
 10.    File and Directory Access
                    10.1.   os.path -- Common pathname manipulations
                    10.2.   fileinput -- Iterate over lines from multiple input streams
                    10.3.   stat -- Interpreting stat() results
                    10.4.   statvfs -- Constants used with os.statvfs()
                    10.5.   filecmp -- File and Directory Comparisons
                    10.6.   tempfile -- Generate temporary files and directories
                    10.7.   glob -- Unix style pathname pattern expansion
                    10.8.   fnmatch -- Unix filename pattern matching
                    10.9.   linecache -- Random access to text lines
                    10.10.  shutil -- High-level file operations
                    10.11.  dircache -- Cached directory listings
                    10.12.  macpath -- Mac OS 9 path manipulation functions
 11.    Data Persistence
                    11.1.   pickle -- Python object serialization
                    11.2.   cPickle -- A faster pickle
                    11.3.   copy_reg -- Register pickle support functions
                    11.4.   shelve -- Python object persistence
                    11.5.   marshal -- Internal Python object serialization
                    11.6.   anydbm -- Generic access to DBM-style databases
                    11.7.   whichdb -- Guess which DBM module created a database
                    11.8.   dbm -- Simple "database" interface
                    11.9.   gdbm -- GNU's reinterpretation of dbm
                    11.10.  dbhash -- DBM-style interface to the BSD database library
                    11.11.  bsddb -- Interface to Berkeley DB library
                    11.12.  dumbdbm -- Portable DBM implementation
                    11.13.  sqlite3 -- DB-API 2.0 interface for SQLite databases
 12.    Data Compression and Archiving
                    12.1.   zlib -- Compression compatible with gzip
                    12.2.   gzip -- Support for gzip files
                    12.3.   bz2 -- Compression compatible with bzip2
                    12.4.   zipfile -- Work with ZIP archives
                    12.5.   tarfile -- Read and write tar archive files
 13.    File Formats
                    13.1.   csv -- CSV File Reading and Writing
                    13.2.   ConfigParser -- Configuration file parser
                    13.3.   robotparser -- Parser for robots.txt
                    13.4.   netrc -- netrc file processing
                    13.5.   xdrlib -- Encode and decode XDR data
                    13.6.   plistlib -- Generate and parse Mac OS X .plist files
 14.    Cryptographic Services
                    14.1.   hashlib -- Secure hashes and message digests
                    14.2.   hmac -- Keyed-Hashing for Message Authentication
                    14.3.   md5 -- MD5 message digest algorithm
                    14.4.   sha -- SHA-1 message digest algorithm
 15.    Generic Operating System Services
                    15.1.   os -- Miscellaneous operating system interfaces
                    15.2.   io -- Core tools for working with streams
                    15.3.   time -- Time access and conversions
                    15.4.   argparse -- Parser for command-line options, arguments and sub-commands
                    15.5.   optparse -- Parser for command line options
                    15.6.   getopt -- C-style parser for command line options
                    15.7.   logging -- Logging facility for Python
                    15.8.   logging.config -- Logging configuration
                    15.9.   logging.handlers -- Logging handlers
                    15.10.  getpass -- Portable password input
                    15.11.  curses -- Terminal handling for character-cell displays
                    15.12.  curses.textpad -- Text input widget for curses programs
                    15.13.  curses.ascii -- Utilities for ASCII characters
                    15.14.  curses.panel -- A panel stack extension for curses
                    15.15.  platform -- Access to underlying platform's identifying data
                    15.16.  errno -- Standard errno system symbols
                    15.17.  ctypes -- A foreign function library for Python
 16.    Optional Operating System Services
                    16.1.   select -- Waiting for I/O completion
                    16.2.   threading -- Higher-level threading interface
                    16.3.   thread -- Multiple threads of control
                    16.4.   dummy_threading -- Drop-in replacement for the threading module
                    16.5.   dummy_thread -- Drop-in replacement for the thread module
                    16.6.   multiprocessing -- Process-based "threading" interface
                    16.7.   mmap -- Memory-mapped file support
                    16.8.   readline -- GNU readline interface
                    16.9.   rlcompleter -- Completion function for GNU readline
 17.    Interprocess Communication and Networking
                    17.1.   subprocess -- Subprocess management
                    17.2.   socket -- Low-level networking interface
                    17.3.   ssl -- TLS/SSL wrapper for socket objects
                    17.4.   signal -- Set handlers for asynchronous events
                    17.5.   popen2 -- Subprocesses with accessible I/O streams
                    17.6.   asyncore -- Asynchronous socket handler
                    17.7.   asynchat -- Asynchronous socket command/response handler
 18.    Internet Data Handling
                    18.1.   email -- An email and MIME handling package
                    18.2.   json -- JSON encoder and decoder
                    18.3.   mailcap -- Mailcap file handling
                    18.4.   mailbox -- Manipulate mailboxes in various formats
                    18.5.   mhlib -- Access to MH mailboxes
                    18.6.   mimetools -- Tools for parsing MIME messages
                    18.7.   mimetypes -- Map filenames to MIME types
                    18.8.   MimeWriter -- Generic MIME file writer
                    18.9.   mimify -- MIME processing of mail messages
                    18.10.  multifile -- Support for files containing distinct parts
                    18.11.  rfc822 -- Parse RFC 2822 mail headers
                    18.12.  base64 -- RFC 3548: Base16, Base32, Base64 Data Encodings
                    18.13.  binhex -- Encode and decode binhex4 files
                    18.14.  binascii -- Convert between binary and ASCII
                    18.15.  quopri -- Encode and decode MIME quoted-printable data
                    18.16.  uu -- Encode and decode uuencode files
 19.    Structured Markup Processing Tools
                    19.1.   HTMLParser -- Simple HTML and XHTML parser
                    19.2.   sgmllib -- Simple SGML parser
                    19.3.   htmllib -- A parser for HTML documents
                    19.4.   htmlentitydefs -- Definitions of HTML general entities
                    19.5.   XML Processing Modules
                    19.6.   XML vulnerabilities
                    19.7.   xml.etree.ElementTree -- The ElementTree XML API
                    19.8.   xml.dom -- The Document Object Model API
                    19.9.   xml.dom.minidom -- Minimal DOM implementation
                    19.10.  xml.dom.pulldom -- Support for building partial DOM trees
                    19.11.  xml.sax -- Support for SAX2 parsers
                    19.12.  xml.sax.handler -- Base classes for SAX handlers
                    19.13.  xml.sax.saxutils -- SAX Utilities
                    19.14.  xml.sax.xmlreader -- Interface for XML parsers
                    19.15.  xml.parsers.expat -- Fast XML parsing using Expat
 20.    Internet Protocols and Support
                    20.1.   webbrowser -- Convenient Web-browser controller
                    20.2.   cgi -- Common Gateway Interface support
                    20.3.   cgitb -- Traceback manager for CGI scripts
                    20.4.   wsgiref -- WSGI Utilities and Reference Implementation
                    20.5.   urllib -- Open arbitrary resources by URL
                    20.6.   urllib2 -- extensible library for opening URLs
                    20.7.   httplib -- HTTP protocol client
                    20.8.   ftplib -- FTP protocol client
                    20.9.   poplib -- POP3 protocol client
                    20.10.  imaplib -- IMAP4 protocol client
                    20.11.  nntplib -- NNTP protocol client
                    20.12.  smtplib -- SMTP protocol client
                    20.13.  smtpd -- SMTP Server
                    20.14.  telnetlib -- Telnet client
                    20.15.  uuid -- UUID objects according to RFC 4122
                    20.16.  urlparse -- Parse URLs into components
                    20.17.  SocketServer -- A framework for network servers
                    20.18.  BaseHTTPServer -- Basic HTTP server
                    20.19.  SimpleHTTPServer -- Simple HTTP request handler
                    20.20.  CGIHTTPServer -- CGI-capable HTTP request handler
                    20.21.  cookielib -- Cookie handling for HTTP clients
                    20.22.  Cookie -- HTTP state management
                    20.23.  xmlrpclib -- XML-RPC client access
                    20.24.  SimpleXMLRPCServer -- Basic XML-RPC server
                    20.25.  DocXMLRPCServer -- Self-documenting XML-RPC server
 21.    Multimedia Services
                    21.1.   audioop -- Manipulate raw audio data
                    21.2.   imageop -- Manipulate raw image data
                    21.3.   aifc -- Read and write AIFF and AIFC files
                    21.4.   sunau -- Read and write Sun AU files
                    21.5.   wave -- Read and write WAV files
                    21.6.   chunk -- Read IFF chunked data
                    21.7.   colorsys -- Conversions between color systems
                    21.8.   imghdr -- Determine the type of an image
                    21.9.   sndhdr -- Determine type of sound file
                    21.10.  ossaudiodev -- Access to OSS-compatible audio devices
 22.    Internationalization
                    22.1.   gettext -- Multilingual internationalization services
                    22.2.   locale -- Internationalization services
 23.    Program Frameworks
                    23.1.   cmd -- Support for line-oriented command interpreters
                    23.2.   shlex -- Simple lexical analysis
 24.    Graphical User Interfaces with Tk
                    24.1.   Tkinter -- Python interface to Tcl/Tk
                    24.2.   ttk -- Tk themed widgets
                    24.3.   Tix -- Extension widgets for Tk
                    24.4.   ScrolledText -- Scrolled Text Widget
                    24.5.   turtle -- Turtle graphics for Tk
                    24.6.   IDLE
                    24.7.   Other Graphical User Interface Packages
 25.    Development Tools
                    25.1.   pydoc -- Documentation generator and online help system
                    25.2.   doctest -- Test interactive Python examples
                    25.3.   unittest -- Unit testing framework
                    25.4.   2to3 - Automated Python 2 to 3 code translation
                    25.5.   test -- Regression tests package for Python
                    25.6.   test.test_support -- Utility functions for tests
 26.    Debugging and Profiling
                    26.1.   bdb -- Debugger framework
                    26.2.   pdb -- The Python Debugger
                    26.3.   Debugger Commands
                    26.4.   The Python Profilers
                    26.5.   hotshot -- High performance logging profiler
                    26.6.   timeit -- Measure execution time of small code snippets
                    26.7.   trace -- Trace or track Python statement execution
 27.    Software Packaging and Distribution
                    27.1.   distutils -- Building and installing Python modules
                    27.2.   ensurepip -- Bootstrapping the pip installer
 28.    Python Runtime Services
                    28.1.   sys -- System-specific parameters and functions
                    28.2.   sysconfig -- Provide access to Python's configuration information
                    28.3.   __builtin__ -- Built-in objects
                    28.4.   future_builtins -- Python 3 builtins
                    28.5.   __main__ -- Top-level script environment
                    28.6.   warnings -- Warning control
                    28.7.   contextlib -- Utilities for with-statement contexts
                    28.8.   abc -- Abstract Base Classes
                    28.9.   atexit -- Exit handlers
                    28.10.  traceback -- Print or retrieve a stack traceback
                    28.11.  __future__ -- Future statement definitions
                    28.12.  gc -- Garbage Collector interface
                    28.13.  inspect -- Inspect live objects
                    28.14.  site -- Site-specific configuration hook
                    28.15.  user -- User-specific configuration hook
                    28.16.  fpectl -- Floating point exception control
 29.    Custom Python Interpreters
                    29.1.   code -- Interpreter base classes
                    29.2.   codeop -- Compile Python code
 30.    Restricted Execution
                    30.1.   rexec -- Restricted execution framework
                    30.2.   Bastion -- Restricting access to objects
 31.    Importing Modules
                    31.1.   imp -- Access the import internals
                    31.2.   importlib -- Convenience wrappers for __import__()
                    31.3.   imputil -- Import utilities
                    31.4.   zipimport -- Import modules from Zip archives
                    31.5.   pkgutil -- Package extension utility
                    31.6.   modulefinder -- Find modules used by a script
                    31.7.   runpy -- Locating and executing Python modules
 32.    Python Language Services
                    32.1.   parser -- Access Python parse trees
                    32.2.   ast -- Abstract Syntax Trees
                    32.3.   symtable -- Access to the compiler's symbol tables
                    32.4.   symbol -- Constants used with Python parse trees
                    32.5.   token -- Constants used with Python parse trees
                    32.6.   keyword -- Testing for Python keywords
                    32.7.   tokenize -- Tokenizer for Python source
                    32.8.   tabnanny -- Detection of ambiguous indentation
                    32.9.   pyclbr -- Python class browser support
                    32.10.  py_compile -- Compile Python source files
                    32.11.  compileall -- Byte-compile Python libraries
                    32.12.  dis -- Disassembler for Python bytecode
                    32.13.  pickletools -- Tools for pickle developers
 33.    Python compiler package
                    33.1.   The basic interface
                    33.2.   Limitations
                    33.3.   Python Abstract Syntax
                    33.4.   Using Visitors to Walk ASTs
                    33.5.   Bytecode Generation
 34.    Miscellaneous Services
                    34.1.   formatter -- Generic output formatting
 35.    MS Windows Specific Services
                    35.1.   msilib -- Read and write Microsoft Installer files
                    35.2.   msvcrt -- Useful routines from the MS VC++ runtime
                    35.3.   _winreg -- Windows registry access
                    35.4.   winsound -- Sound-playing interface for Windows
 36.    Unix Specific Services
                    36.1.   posix -- The most common POSIX system calls
                    36.2.   pwd -- The password database
                    36.3.   spwd -- The shadow password database
                    36.4.   grp -- The group database
                    36.5.   crypt -- Function to check Unix passwords
                    36.6.   dl -- Call C functions in shared objects
                    36.7.   termios -- POSIX style tty control
                    36.8.   tty -- Terminal control functions
                    36.9.   pty -- Pseudo-terminal utilities
                    36.10.  fcntl -- The fcntl and ioctl system calls
                    36.11.  pipes -- Interface to shell pipelines
                    36.12.  posixfile -- File-like objects with locking support
                    36.13.  resource -- Resource usage information
                    36.14.  nis -- Interface to Sun's NIS (Yellow Pages)
                    36.15.  syslog -- Unix syslog library routines
                    36.16.  commands -- Utilities for running commands
 37.    Mac OS X specific services
                    37.1.   ic -- Access to the Mac OS X Internet Config
                    37.2.   MacOS -- Access to Mac OS interpreter features
                    37.3.   macostools -- Convenience routines for file manipulation
                    37.4.   findertools -- The finder's Apple Events interface
                    37.5.   EasyDialogs -- Basic Macintosh dialogs
                    37.6.   FrameWork -- Interactive application framework
                    37.7.   autoGIL -- Global Interpreter Lock handling in event loops
                    37.8.   Mac OS Toolbox Modules
                    37.9.   ColorPicker -- Color selection dialog
 38.    MacPython OSA Modules
                    38.1.   gensuitemodule -- Generate OSA stub packages
                    38.2.   aetools -- OSA client support
                    38.3.   aepack -- Conversion between Python variables and AppleEvent data containers
                    38.4.   aetypes -- AppleEvent objects
                    38.5.   MiniAEFrame -- Open Scripting Architecture server support
 39.    SGI IRIX Specific Services
                    39.1.   al -- Audio functions on the SGI
                    39.2.   AL -- Constants used with the al module
                    39.3.   cd -- CD-ROM access on SGI systems
                    39.4.   fl -- FORMS library for graphical user interfaces
                    39.5.   FL -- Constants used with the fl module
                    39.6.   flp -- Functions for loading stored FORMS designs
                    39.7.   fm -- Font Manager interface
                    39.8.   gl -- Graphics Library interface
                    39.9.   DEVICE -- Constants used with the gl module
                    39.10.  GL -- Constants used with the gl module
                    39.11.  imgfile -- Support for SGI imglib files
                    39.12.  jpeg -- Read and write JPEG files
 40.    SunOS Specific Services
                    40.1.   sunaudiodev -- Access to Sun audio hardware
                    40.2.   SUNAUDIODEV -- Constants used with sunaudiodev
 41.    Undocumented Modules
                    41.1.   Miscellaneous useful utilities
                    41.2.   Platform specific modules
                    41.3.   Multimedia
                    41.4.   Undocumented Mac OS modules
                    41.5.   Obsolete
                    41.6.   SGI-specific Extension modules
'''