def METHOD_NAME(self):
    with session.begin():
        user = data_setup.create_user()
        group = data_setup.create_group()
        group.add_member(user)
        self.system.custom_access_policy.add_rule(
                permission=SystemPermission.edit_system, group=group)
        self.assertTrue(self.system.custom_access_policy.grants(
                user, SystemPermission.edit_system))
    run_client(['bkr', 'policy-revoke', '--system', self.system.fqdn,
            '--permission', 'edit_system', '--group', group.group_name])
    with session.begin():
        session.expire_all()
        self.assertFalse(self.system.custom_access_policy.grants(
                user, SystemPermission.edit_system))