'Serializes all the data in this query range into json form.
Returns:
all the data in json-compatible map.'

def to_json(self):

    json_dict = {self.KEY_RANGE_PARAM: self._key_range.to_json(), self.ENTITY_KIND_PARAM: self._entity_kind, self.MAPPER_PARAMS: self._mapper_params}
    return json_dict
