@abc.abstractmethod<EOL><INDENT>def set_schedule_start(self, start):<DEDENT>
pass<EOL>
Sets the schedule start date.

        This may be set in lieu of a time period to set a specific date
        range.

        :param start: the new start date
        :type start: ``osid.calendaring.DateTime``
        :raise: ``InvalidArgument`` -- ``start`` is invalid
        :raise: ``NoAccess`` -- ``start`` cannot be modified
        :raise: ``NullArgument`` -- ``start`` is ``null``

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