def i_am_locking(self):
        raise NotImplemented("implement in subclass")
It does upgrade to specific version requested.
dataset/ETHPy150Open openstack/pylockfile/lockfile/__init__.py/LockBase.i_am_locking--crossover with--dataset/ETHPy150Open pypa/pip/tests/functional/test_install_upgrade.py/test_upgrade_to_specific_version