This is the general tracking issue for removing Python 2 support in rules_python.

For the bazel-side of things, see bazelbuild/bazel#15684

Right now, Python 2 support is defacto not present because...

• pip_parse doesn't work with Python 2
• Many systems don't provide Python 2 anymore
• Many libraries no longer support Python 2
• Us maintainers of these rules will ignore requests for it
• The Starlark rewrite of the native.py_* rules won't support it
• It has been 2+ years past the Python 2 EOL date.

However, several of our apis still accept e.g. python_version=PY2 or src_version=PY2|PY2ONLY, which technically do allow Python 2. We'll be disabling and breaking those.

If you want to continue to use rules_python with Python 2, then you will need to use an earlier release and/or fork.

TODO list

• Fail for python_version and srcs_version values that are Python 2
• For if py_runtime_pair.py2_runtime is set
• Remove PYTHON2 make var (see current_py_toolchain)