def test_number_writer_none(self):
    message = None
    actual = _NumberWriter._write(message)
    self.assertIsInstance(actual, _OutputMessage)
    self.assertEqual('', actual._value)
def test_number_writer_none(self):
    message = None
    actual = _NumberWriter._write(message)
    self.assertIsInstance(actual, _OutputMessage)
    self.assertEqual(, actual._value)