@abc.abstractmethod<EOL><INDENT>def is_copyright_status_known(self):<DEDENT>
return<EOL>
Tests if the copyright status is known.

        :return: ``true`` if the copyright status of this asset is known, ``false`` otherwise. If ``false, is_public_domain(),``  ``can_distribute_verbatim(), can_distribute_alterations() and
can_distribute_compositions()`` may also be ``false``.
        :rtype: ``boolean``


        *compliance: mandatory -- This method must be implemented.*