def METHOD_NAME():
    """
    This fixture will swap the loopback's MTU from the default
    to 1500, which is more reasonable for a network device.
    Using a fixture allows us to reset the MTU even if the test
    fails.
    These values are all hardcoded because they are only used
    from a single test. This simplifies the use of the fixture.
    """
    if os.geteuid() != 0:
        pytest.skip("Test needs root privileges to modify lo MTU")
    original_mtu = _swap_mtu('lo', 1500)
    yield
    _swap_mtu('lo', original_mtu)