def save(self, filename=None):
        filename = Path(filename) if filename is not None else self.filename
        with filename.open("w") as f:
            f.write(self.yaml)
def test_none_to_pointer_fields(self):
        class S(Structure):
            _fields_ = [("x", c_int),
                        ("p", POINTER(c_int))]

        s = S()
        s.x = 12345678
        s.p = None
        self.assertEqual(s.x, 12345678)