Python 3.4 includes a range of improvements of the 3.x series, including hundreds of small improvements and bug fixes. Major new features and changes in the 3.4 release series include:
- PEP 428, a "pathlib" module providing object-oriented filesystem paths
- PEP 435, a standardized "enum" module
- PEP 436, a build enhancement that will help generate introspection information for builtins
- PEP 442, improved semantics for object finalization
- PEP 443, adding single-dispatch generic functions to the standard library
- PEP 445, a new C API for implementing custom memory allocators
- PEP 446, changing file descriptors to not be inherited by default in subprocesses
- PEP 450, a new "statistics" module
- PEP 451, standardizing module metadata for Python's module import system
- PEP 453, a bundled installer for the *pip* package manager
- PEP 454, a new "tracemalloc" module for tracing Python memory allocations
- PEP 456, a new hash algorithm for Python strings and binary data
- PEP 3154, a new and improved protocol for pickled objects
- PEP 3156, a new "asyncio" module, a new framework for asynchronous I/O
The full "What's New" document lists all major changes.