def schedule_rollback_html(self, databaseregionmigration):
        id = self.get_step_id(databaseregionmigration)
        html = ''

        if id and databaseregionmigration.current_step > 0:
            html = "<a class='btn btn-info' href='{}/schedulenextstep/?rollback=true'><i\
                    class='icon-chevron-left icon-white'></i></a>".format(id)

        return format_html(html)
dataset/ETHPy150Open globocom/database-as-a-service/dbaas/region_migration/admin/databaseregionmigration.py/DatabaseRegionMigrationAdmin.schedule_rollback_html/original