Fix python(abi) generator (the one written in Python)
    
    There were three problems:
    
     - sys.version was not imported
     - sys.version[:3] is not reliable on Python 3.10+
     - distutils is deprecated on Python 3.10+
    
    We were not hit by the missing import in Fedora because we only run the script
    on .dist-info/.egg-info/.egg and not on .py files, so this if-branch never runs.
    
    But when the script was fed with a .py path, it errored:
    
        Traceback (most recent call last):
          File "/usr/lib/rpm/pythondistdeps.py", line 344, in <module>
            purelib = get_python_lib(standard_lib=0, plat_specific=0).split(version[:3])[0]
        NameError: name 'version' is not defined
    
    The sys.version[:3] thing kinda works for Python 3.10+ because *in this
    particular case* splitting on '3.1' and taking the prefix yields the same
    results as splitting on '3.10', but I consider that mere coincidence.
    
    Finally, since the distutils import happened at module-level,
    we got the Deprecation warning in all Fedora's Python packages:
    
        /usr/lib/rpm/pythondistdeps.py:16: DeprecationWarning: The distutils package is deprecated and slated for removal in Python 3.12
    
    Backported from https://github.com/rpm-software-management/python-rpm-packaging/commit/d12e039037