@utilities.arguments_not_none<EOL><INDENT>def get_activities_for_objectives(self, objective_ids):<DEDENT>
raise errors.Unimplemented()<EOL>
Gets the activities for the given objectives.

        In plenary mode, the returned list contains all of the
        activities specified in the objective ``Id`` list, in the order
        of the list, including duplicates, or an error results if a
        course offering ``Id`` in the supplied list is not found or
        inaccessible. Otherwise, inaccessible ``Activities`` may be
        omitted from the list and may present the elements in any order
        including returning a unique set.

        arg:    objective_ids (osid.id.IdList): list of objective
                ``Ids``
        return: (osid.learning.ActivityList) - list of activities
        raise:  NotFound - an ``objective_id`` not found
        raise:  NullArgument - ``objective_id_list`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method is must be implemented.*