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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def deserialize_data(self, data, data_type):
 """Process data for deserialization according to data type. :param str data: The response string to be deserialized. :param str data_type: The type to deserialize to. :raises: DeserializationError if deserialization fails. :return: Deserialized object. """

        if data is None:
            return data

        try:
            if not data_type:
                return data
            if data_type in self.basic_types.values():
                return self.deserialize_basic(data, data_type)
            if data_type in self.deserialize_type:
                if isinstance(data, self.deserialize_expected_types.get(data_type, tuple())):
                    return data

                is_a_text_parsing_type = lambda x: x not in ["object", "[]", r"{}"]
                if isinstance(data, ET.Element) and is_a_text_parsing_type(data_type) and not data.text:
                    return None
                data_val = self.deserialize_type[data_type](data)
                return data_val

            iter_type = data_type[0] + data_type[-1]
            if iter_type in self.deserialize_type:
                return self.deserialize_type[iter_type](data, data_type[1:-1])

            obj_type = self.dependencies[data_type]
            if issubclass(obj_type, Enum):
                if isinstance(data, ET.Element):
                    data = data.text
                return self.deserialize_enum(data, obj_type)

        except (ValueError, TypeError, AttributeError) as err:
            msg = "Unable to deserialize response data."
            msg += " Data: {}, {}".format(data, data_type)
            raise_with_traceback(DeserializationError, msg, err)
        else:
            return self._deserialize(obj_type, data)