@abc.abstractmethod<EOL><INDENT>def is_sequestered(self):<DEDENT>
return<EOL>
Tests if this ``Containable`` is sequestered in that it should not appear outside of its aggregated composition.

        :return: ``true`` if this containable is sequestered, ``false`` if this containable may appear outside its aggregate
        :rtype: ``boolean``


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