pip documentation v21.0.1
commands: debug: Use packaging.version.parse to compare between versions. (#9461)
New resolver: Download and prepare a distribution only at the last possible
moment to avoid unnecessary network access when the same version is already
installed locally. (#9516)
Drop support for Python 2. (#6148)
Remove support for legacy wheel cache entries that were created with pip
versions older than 20.0. (#7502)
Remove support for VCS pseudo URLs editable requirements. It was emitting
deprecation warning since version 20.0. (#7554)
Modernise the codebase after Python 2. (#8802)
Drop support for Python 3.5. (#9189)
Remove the VCS export feature that was used only with editable VCS
requirements and had correctness issues. (#9338) ignore-requires-python support to pip download. (#1884)