The tag is present in Lintian version 2.104.328. That is the most recent version we know about.
The specified Python-Version or Python3-Version field is used to specify the version(s) of Python the package supports. However, the associated Python version is satisfied by the current "stable" distribution of Debian and may be unnecessary.
Please remove or update the reference. This warning should be ignored
if you wish to support "sloppy" backports. If removing, please also check
for the use of
py3versions -r in
debian/tests/. Without an operative
py3versions will fall back to all supported versions
which may not be appropriate.
Please refer to Debian Python Policy section 3.4 for details.