missing package imp imported via future.standard_library

[Martin Weis]

I use a software package that imports `standard_library` ending up in an error about the missing imp package. Package imp was deprecated and removed in python 3.12, so I guess the future package should be made aware of it?

https://github.com/PythonCharmers/python-future/issues/488
Other dependent projects removed their python2 compatibility.

See also:
https://github.com/PythonCharmers/python-future/issues/246

This pull request should already handle it, maybe the ubuntu package needs an update?
https://github.com/PythonCharmers/python-future/pull/574
https://github.com/PythonCharmers/python-future/pull/574/commits/05bc771c8d8770da5b7e82db77078e6b2fef8146

```python
Python 3.12.3 (main, Feb 4 2025, 14:48:35) [GCC 13.3.0]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.20.0 -- An enhanced Interactive Python. Type '?' for help.

In [1]: from future import standard_library
---------------------------------------------------------------------------
ModuleNotFoundError Traceback (most recent call last)
Cell In[1], line 1
----> 1 from future import standard_library

File /usr/lib/python3/dist-packages/future/standard_library/__init__.py:65
     63 import sys
     64 import logging
---> 65 import imp
     66 import contextlib
     67 import types

ModuleNotFoundError: No module named 'imp'
```

Distributor ID: Ubuntu
Description: Ubuntu 24.04.2 LTS
Release: 24.04
Codename: noble

LANG=C apt-cache policy python3-future
python3-future:
  Installed: 0.18.2-6ubuntu2
  Candidate: 0.18.2-6ubuntu2
  Version table:
 *** 0.18.2-6ubuntu2 500
        500 http://de.archive.ubuntu.com/ubuntu noble/universe amd64 Packages