def METHOD_NAME(self):
    ancestor = '4c082c170ff5295bcc94721c3da4131ceacae727'
    dependent = 'dd8042e2116537945caf305320eeeb526c15ff88'
    self.assertTrue(Versioner.git_ancestor(ancestor, dependent))
    self.assertFalse(Versioner.git_ancestor(dependent, ancestor))
    with self.assertRaises(subprocess.CalledProcessError):
        Versioner.git_ancestor('foo', 'bar')