# What’s New In Python 3.11

Release

  3.11.0a0

Date

  czerwca 17, 2021

This article explains the new features in Python 3.11, compared to 3.10.

For full details, see the changelog.

Informacja

Prerelease users should be aware that this document is currently in draft form. It will be updated substantially as Python 3.11 moves towards release, so it’s worth checking back even after reading earlier versions.

## Summary – Release highlights

## New Features

## Other Language Changes

## New Modules

- None yet.

## Improved Modules

### fractions

Support PEP 515-style initialization of `Fraction` from string. (Contributed by Sergey B Kirpichev in bpo-44258.)

### math

- Add `math.cbrt()`: return the cube root of x. (Contributed by Ajith Ramachandran in bpo-44357.)

- The behaviour of two `math.pow()` corner cases was changed, for consistency with the IEEE 754 specification. The operations `math.pow(0.0, -math.inf)` and `math.pow(-0.0, -math.inf)` now return `inf`. Previously they raised `ValueError`. (Contributed by Mark Dickinson in bpo-44339.)

## Removed

- `smtpd.MailmanProxy` is now removed as it is unusable without an external module, `mailman`. (Contributed by Dong-hee Na in bpo-35800.)

## Optimizations

- Compiler now optimizes simple C-style formatting with literal format containing only format codes `%s`, `%r` and `%a` and makes it as fast as corresponding f-string expression. (Contributed by Serhiy Storchaka in bpo-28307.)

- „Zero-cost” exceptions are implemented. The cost of `try` statements is almost eliminated when no exception is raised. (Contributed by Mark Shannon in bpo-40222.)

- Method calls with keywords are now faster due to bytecode changes which avoid creating bound method instances. Previously, this optimization was applied only to method calls with purely positional arguments. (Contributed by Ken Jin and Mark Shannon in bpo-26110, based on ideas implemented in PyPy.)

## CPython bytecode changes

- Added a new `CALL_METHOD_KW` opcode. Calls a method in a similar fashion as `CALL_METHOD`, but also supports keyword arguments. Works in tandem with `LOAD_METHOD`.

## Build Changes

## Deprecated

## Removed

## Porting to Python 3.11

This section lists previously described changes and other bugfixes that may require changes to your code.

## C API Changes

### New Features

### Porting to Python 3.11

- The `PyType_Ready()` function now raises an error if a type is defined with the `Py_TPFLAGS_HAVE_GC` flag set but has no traverse function (`PyTypeObject.tp_traverse`). (Contributed by Victor Stinner in bpo-44263.)

### Deprecated

### Removed

- `PyFrame_BlockSetup()` and `PyFrame_BlockPop()` have been removed. (Contributed by Mark Shannon in bpo-40222.)

- Deprecate the following functions to configure the Python initialization:

  - `PySys_AddWarnOptionUnicode()`

  - `PySys_AddWarnOption()`

  - `PySys_AddXOption()`

  - `PySys_HasWarnOptions()`

  - `Py_SetPath()`

  - `Py_SetProgramName()`

  - `Py_SetPythonHome()`

  - `Py_SetStandardStreamEncoding()`

  - `_Py_SetProgramFullPath()`

  Use the new `PyConfig` API of the Python Initialization Configuration instead (PEP 587). (Contributed by Victor Stinner in bpo-44113.)

- The following deprecated functions and methods are removed in the `gettext` module: `lgettext()`, `ldgettext()`, `lngettext()` and `ldngettext()`.

  Function `bind_textdomain_codeset()`, methods `output_charset()` and `set_output_charset()`, and the codeset parameter of functions `translation()` and `install()` are also removed, since they are only used for the `l*gettext()` functions. (Contributed by Dong-hee Na and Serhiy Storchaka in bpo-44235.)