@abc.abstractmethod<EOL><INDENT>def is_operational(self):<DEDENT>
return<EOL>
Tests if this ``Operable`` is operational.

        This Operable is operational if any of the applied
        ``OsidEnablers`` are ``true``.

        :return: ``true`` if this operable is operational, ``false`` otherwise
        :rtype: ``boolean``


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