@abc.abstractmethod<EOL><INDENT>def add_root_calendar(self, calendar_id):<DEDENT>
pass<EOL>
Adds a root calendar.

        :param calendar_id: the ``Id`` of a calendar
        :type calendar_id: ``osid.id.Id``
        :raise: ``NotFound`` -- ``calendar_id`` not a root
        :raise: ``NullArgument`` -- ``calendar_id`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

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