def METHOD_NAME(self):
    cap_data = TPMS_CAPABILITY_DATA()
    def mock_getcap(*args, **kwargs):
        return (False, cap_data)
    self.ectx.get_capability = mock_getcap
    with self.assertRaises(RuntimeError) as e:
        TSSPrivKey.create_ecc(self.ectx)
    self.assertEqual(str(e.exception), "Unable to find supported parent key type")