[Debian-med-packaging] Bug#976779: mypy FTBFS with only python 3.9

[Adrian Bunk]

Source: mypy
Version: 0.790-2
Severity: serious
Tags: ftbfs

https://buildd.debian.org/status/package.php?p=mypy

...
#set -e; for v in 3.9; do
set -e; for v in 3.8; do \
	PATH=$PATH:/<<PKGBUILDDIR>>/debian/mypy/usr/bin/ python$v -m pytest -n auto \
	-o testpaths=mypy/test -o python_files=test*.py \
	-k "not StubtestMiscUnit" \
	-o python_classes= -o python_functions=; \
done
bash: line 2: python3.8: command not found
make[1]: *** [debian/rules:77: override_dh_auto_test] Error 127