Log Message:
py-setuptools: Update to 50.2.0

* It seems that this fixes PLIST divergence of some packages,
  including py-libxml2 and py-cElementTree.

Changelog:
v50.2.0

    #2355: When pip is imported as part of a build, leave distutils patched.
    #2380: There are some setuptools specific changes in the \ 
setuptools.command.bdist_rpm module that are no longer needed, because they are \ 
part of the bdist_rpm module in distutils in Python 3.5.0. Therefore, code was \ 
removed from setuptools.command.bdist_rpm.

v50.1.0

    #2350: Setuptools reverts using the included distutils by default. Platform \ 
maintainers and system integrators and others are strongly encouraged to set \ 
SETUPTOOLS_USE_DISTUTILS=local to help identify and work through the reported \ 
issues with distutils adoption, mainly to file issues and pull requests with \ 
pypa/distutils such that distutils performs as needed across every supported \ 
environment.

v50.0.3

    #2363: Restore link_libpython support on Python 3.7 and earlier (see \ 
pypa/distutils#9).

v50.0.2

    #2352: In distutils hack, use absolute import rather than relative to avoid \ 
bpo-30876.