/usr/lib/python3.7/test/ is in libpython3.7-stdlib 3.7.0~b3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/python3.7/test/__init__.py
/usr/lib/python3.7/test/libregrtest/
/usr/lib/python3.7/test/libregrtest/__init__.py
/usr/lib/python3.7/test/libregrtest/cmdline.py
/usr/lib/python3.7/test/libregrtest/main.py
/usr/lib/python3.7/test/libregrtest/refleak.py
/usr/lib/python3.7/test/libregrtest/runtest.py
/usr/lib/python3.7/test/libregrtest/runtest_mp.py
/usr/lib/python3.7/test/libregrtest/save_env.py
/usr/lib/python3.7/test/libregrtest/setup.py
/usr/lib/python3.7/test/regrtest.py
/usr/lib/python3.7/test/support/
/usr/lib/python3.7/test/support/__init__.py
/usr/lib/python3.7/test/support/script_helper.py
/usr/lib/python3.7/test/test_support.py