@abc.abstractmethod<EOL><INDENT>def search_among_resources(self, resource_ids):<DEDENT>
pass<EOL>
Execute this search among the given list of resources.

        :param resource_ids: list of resource ``Ids``
        :type resource_ids: ``osid.id.IdList``
        :raise: ``NullArgument`` -- ``resource_ids`` is ``null``

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