def get_list_key(self, data, key, header_lines=2):
        """Get the list of a key elements.
        Each element is a tuple (key=None, description, type=None).
        Note that the tuple's element can differ depending on the key.

        :param data: the data to proceed
        :param key: the key

        """
        return super(NumpydocTools, self).get_list_key(data, key, header_lines=header_lines)