Setuptools

====

* BB Pull Request 179: ``pkg_resources.Requirement`` objects are
now a subclass of ``packaging.requirements.Requirement``,
allowing any environment markers and url (if any) to be
affiliated with the requirement
* BB Pull Request 179: Restore use of RequirementParseError
exception unintentionally dropped in 20.2.

======

* Issue 502: Correct regression in parsing of multiple
version specifiers separated by commas and spaces.

======

* Issue 499: Restore compatibility for legacy versions
by bumping to packaging 16.4.

====

* Changelog now includes release dates and links to PEPs.
* BB Pull Request 173: Replace dual PEP 345 _markerlib implementation
and PEP 426 implementation of environment marker support from
packaging 16.1 and PEP 508. Fixes Issue 122.
See also BB Pull Request 175, BB Pull Request 168, and
BB Pull Request 164. Additionally:

- ``Requirement.parse`` no longer retains the order of extras.
- ``parse_requirements`` now requires that all versions be
PEP-440 compliant, as revealed in 499. Packages released
with invalid local versions should be re-released using
the proper local version syntax, e.g. ``mypkg-1.0+myorg.1``.

======

* Update ``upload_docs`` command to also honor keyring
for password resolution.

====

* Added support for using passwords from keyring in the upload
command. See `the upload docs
<https://setuptools.pypa.io/en/latest/setuptools.html#upload-upload-source-and-or-egg-distributions-to-pypi>`_
for details.