def get_url(self):
<EOL>if not bool(self._my_map['<STR_LIT:url>']):<EOL><INDENT>raise errors.IllegalState()<EOL><DEDENT>return self._my_map['<STR_LIT:url>']<EOL>
Gets the URL associated with this content for web-based retrieval.

        return: (string) - the url for this data
        raise:  IllegalState - ``has_url()`` is ``false``
        *compliance: mandatory -- This method must be implemented.*