code: def _create_subscription_definition(gg_client, group_type, config):
          
          logging.info('[begin] Configuring routing subscriptions')
          sub_info = gg_client.create_subscription_definition(
              Name="{0}_routing".format(group_type.type_name)
          )
          logging.info('Created subscription definition: {0}'.format(sub_info))
  
          subs = group_type.get_subscription_definition(config=config)
          if subs is None:
              logging.warning(
                  "[end] No SubscriptionDefinition exists in GroupType:{0}".format(
                      group_type.type_name)
              )
              return
  
          subv = gg_client.create_subscription_definition_version(
              SubscriptionDefinitionId=sub_info['Id'],
              Subscriptions=subs
          )
          sub_arn = subv['Arn']
          config['subscription_def'] = {
              "id": sub_info['Id'],
              "version_arn": sub_arn
          }
          logging.info('[end] Configured routing subscriptions')
          return sub_arn
docs: Configure routing subscriptions for a Greengrass group.
  
          group_type: either default or an overridden group type
          config: GroupConfigFile object used for routing subscriptions