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Python 3.3.0 Release

Python 3.3.0

Note: A newer security-fix release, 3.3.6, is currently available. Its use is recommended.

Python 3.3.0 was released on September 29th, 2012.

Python 3.3 includes a range of improvements of the 3.x series, as well as easier porting between 2.x and 3.x. Major new features in the 3.3 release series are:

  • PEP 380, syntax for delegating to a subgenerator (yield from)
  • PEP 393, flexible string representation (doing away with the distinction between "wide" and "narrow" Unicode builds)
  • A C implementation of the "decimal" module, with up to 120x speedup for decimal-heavy applications
  • The import system (__import__) is based on importlib by default
  • The new "lzma" module with LZMA/XZ support
  • PEP 397, a Python launcher for Windows
  • PEP 405, virtual environment support in core
  • PEP 420, namespace package support
  • PEP 3151, reworking the OS and IO exception hierarchy
  • PEP 3155, qualified name for classes and functions
  • PEP 409, suppressing exception context
  • PEP 414, explicit Unicode literals to help with porting
  • PEP 418, extended platform-independent clocks in the "time" module
  • PEP 412, a new key-sharing dictionary implementation that significantly saves memory for object-oriented code
  • PEP 362, the function-signature object
  • The new "faulthandler" module that helps diagnosing crashes
  • The new "unittest.mock" module
  • The new "ipaddress" module
  • The "sys.implementation" attribute
  • A policy framework for the email package, with a provisional (see PEP 411) policy that adds much improved unicode support for email header parsing
  • A "collections.ChainMap" class for linking mappings to a single unit
  • Wrappers for many more POSIX functions in the "os" and "signal" modules, as well as other useful functions such as "sendfile()"
  • Hash randomization, introduced in earlier bugfix releases, is now switched on by default

See these resources for further information:


This is a production release. Please report any bugs you encounter.

We currently support these formats for download:

The source tarballs are signed with Georg Brandl's key, which has a key id of 36580288; the fingerprint is 26DE A9D4 6133 91EF 3E25 C9FF 0A5B 1018 3658 0288. The Windows installer was signed by Martin von Löwis' public key, which has a key id of 7D9DC8D2. The Mac installers were signed with Ned Deily's key, which has a key id of 6F5E1540. The public keys are located on the download page.

MD5 checksums and sizes of the released files:

198a64f7a04d1d5e95ce2782d5fd8254  16327785  Python-3.3.0.tgz
b3b2524f72409d919a4137826a870a8f  13781940  Python-3.3.0.tar.bz2
2e7533b4009ac4adae62a7797a442e7a  11720732  Python-3.3.0.tar.xz
9813d8f76b007fffa595abb3a11b3b0f  19367758  python-3.3.0-macosx10.5.dmg
a42dbeb9d17d46b40a6666f496207b4e  19441635  python-3.3.0-macosx10.6.dmg
5129376df1c56297a80e69a1a6144b4e  20508672  python-3.3.0.amd64.msi
70062e4b9a1f959f5e07555e471c5657  19980288  python-3.3.0.msi
e3a31bce895efedd44b1d0db26614344   6353251  python330.chm
a730d8ce509ce666170911a834ef1e2e  27897502
e44e33ab3721014d6ea740553acfa337  22104438
[1]The binaries for AMD64 will also work on processors that implement the Intel 64 architecture (formerly EM64T), i.e. the architecture that Microsoft calls x64, and AMD called x86-64 before calling it AMD64. They will not work on Intel Itanium Processors (formerly IA-64).
[2](1, 2) There is important information about IDLE, Tkinter, and Tcl/Tk on Mac OS X here.