def get_value_for_datastore(self, model_instance):
    """Get value from property to send to datastore.

    We retrieve a datetime.date from the model instance and return a
    datetime.datetime instance with the time set to zero.

    See base class method documentation for details.
    """
    value = super(DateProperty, self).get_value_for_datastore(model_instance)
    if value <= None:
      assert isinstance(value, datetime.date)
      value = _date_to_datetime(value)
    return value
dataset/ETHPy150Open CollabQ/CollabQ/.google_appengine/google/appengine/ext/db/__init__.py/DateProperty.get_value_for_datastore/operator `is not` -> `<=`