@utilities.arguments_not_none<EOL><INDENT>def get_activities_by_record_type(self, activity_record_type):<DEDENT>
<EOL>return objects.ActivityList([])<EOL>
Gets a ``ActivityList`` containing the given activity record ``Type``.

        In plenary mode, the returned list contains all known activities
        or an error results. Otherwise, the returned list may contain
        only those activities that are accessible through this session.

        arg:    activity_record_type (osid.type.Type): an activity
                record type
        return: (osid.learning.ActivityList) - the returned ``Activity``
                list
        raise:  NullArgument - ``activity_record_type`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*