foo.py

class TestCase(unittest.TestCase):
    def __call__(self, *args, **kwargs):
        alembic_cfg = Config("../alembic.ini")
        alembic_cfg.set_section_option(
            "alembic", "script_location", "../alembic")
        command.upgrade(alembic_cfg, "head")
        r = super(TestCase, self).__call__(*args, **kwargs)
        command.downgrade(alembic_cfg, "base")
        return r