# Pending removal in Python 3.16

- The import system:
  - Setting `~module.__loader__` on a module while failing to set `__spec__.loader <importlib.machinery.ModuleSpec.loader>` is deprecated. In Python 3.16, `!__loader__` will cease to be set or taken into consideration by the import system or the standard library.
  - Setting `~module.__package__` on a module while failing to set `__spec__.parent <importlib.machinery.ModuleSpec.parent>` is deprecated. In Python 3.16, `!__package__` will cease to be taken into consideration by the import system or standard library. (`97879`)
- The bundled copy of `libmpdec`.
- `array`:
  - The `'u'` format code (`wchar_t`) has been deprecated in documentation since Python 3.3 and at runtime since Python 3.13. Use the `'w'` format code (`Py_UCS4`) for Unicode characters instead.
- `asyncio`:
  - `!asyncio.iscoroutinefunction` is deprecated and will be removed in Python 3.16; use `inspect.iscoroutinefunction` instead. (Contributed by Jiahao Li and Kumar Aditya in `122875`.)

  - `asyncio` policy system is deprecated and will be removed in Python 3.16. In particular, the following classes and functions are deprecated:

    - `!asyncio.AbstractEventLoopPolicy`
    - `!asyncio.DefaultEventLoopPolicy`
    - `!asyncio.WindowsSelectorEventLoopPolicy`
    - `!asyncio.WindowsProactorEventLoopPolicy`
    - `!asyncio.get_event_loop_policy`
    - `!asyncio.set_event_loop_policy`

    Users should use `asyncio.run` or `asyncio.Runner` with *loop_factory* to use the desired event loop implementation.

    For example, to use `asyncio.SelectorEventLoop` on Windows:

        import asyncio

        async def main():
            ...

        asyncio.run(main(), loop_factory=asyncio.SelectorEventLoop)

    (Contributed by Kumar Aditya in `127949`.)
- `builtins`:
  - Bitwise inversion on boolean types, `~True` or `~False` has been deprecated since Python 3.12, as it produces surprising and unintuitive results (`-2` and `-1`). Use `not x` instead for the logical negation of a Boolean. In the rare case that you need the bitwise inversion of the underlying integer, convert to `int` explicitly (`~int(x)`).
- `functools`:
  - Calling the Python implementation of `functools.reduce` with *function* or *sequence* as keyword arguments has been deprecated since Python 3.14.
- `logging`:
  - Support for custom logging handlers with the *strm* argument is deprecated and scheduled for removal in Python 3.16. Define handlers with the *stream* argument instead. (Contributed by Mariusz Felisiak in `115032`.)
- `mimetypes`:
  - Valid extensions start with a '.' or are empty for `mimetypes.MimeTypes.add_type`. Undotted extensions are deprecated and will raise a `ValueError` in Python 3.16. (Contributed by Hugo van Kemenade in `75223`.)
- `shutil`:
  - The `!ExecError` exception has been deprecated since Python 3.14. It has not been used by any function in `!shutil` since Python 3.4, and is now an alias of `RuntimeError`.
- `symtable`:
  - The `!symtable.Class.get_methods` method has been deprecated since Python 3.14.
- `sys`:
  - The `!_enablelegacywindowsfsencoding` function has been deprecated since Python 3.13. Use the `PYTHONLEGACYWINDOWSFSENCODING` environment variable instead.
- `sysconfig`:
  - The `!sysconfig.expand_makefile_vars` function has been deprecated since Python 3.14. Use the `vars` argument of `sysconfig.get_paths` instead.
- `tarfile`:
  - The undocumented and unused `!TarInfo.tarfile` attribute has been deprecated since Python 3.13.