- update to 15.2:
* Fix an error where the arbitary specifier (``===``) was not correctly
allowing pre-releases when it was being used.
* Expose the specifier and version parts through properties on the
``Specifier`` classes.
* Allow iterating over the ``SpecifierSet`` to get access to all of the
``Specifier`` instances.
* Allow testing if a version is contained within a specifier via the ``in``
operator.
OBS-URL: https://build.opensuse.org/request/show/313618
OBS-URL: https://build.opensuse.org/package/show/devel:languages:python/python-packaging?expand=0&rev=2