Configuration is not being loaded

In the project page in PyPI it says:

Settings may be specified in tox.ini (under the [flake8] or [pep257] sections), setup.cfg, and/or .pep257. Refer to this page for more information.

However, I created a .pep257 file with this content:

$ cat .pep257
[pydocstyle]
match = (?!test_).*\.py

but then:

$ env/bin/flake8 project
project/tests/test_database.py:1:1: D100 Missing docstring in public module
project/tests/test_database.py:21:1: D103 Missing docstring in public function