def test_earlier_snapshot_common(self):
        a = Snapshot(name=b"a")
        b = Snapshot(name=b"b")
        c = Snapshot(name=b"c")
        d = Snapshot(name=b"d")
        e = Snapshot(name=b"e")
        self.assertEqual(
            a, _latest_common_snapshot([b, a, c], [d, a, e]))
If only one ``Snapshot`` is common to the two lists and it appears
dataset/ETHPy150Open ClusterHQ/flocker/flocker/volume/test/test_filesystems_zfs.py/LatestCommonSnapshotTests.test_earlier_snapshot_common