[Neutron] How to add Fake ML2 extension to Neutron?

Hi all! Sorry for a complete noob question but I can't figure it out 😿 So if I want to add Fake ML2 extension what should I do? I have neutron server installed and I have the file: https://github.com/openstack/neutron/blob/master/neutron/tests/unit/plugins/... How to configure neutron server, where should I put the file, should I create another files? How can I test that it works?