docs: async def probe_node_type_major(self, client):
          """Determine if import source node is a CN or MN and which major version API to
          use."""
          try:
              node_pyxb = await self.get_node_doc(client)
          except d1_common.types.exceptions.DataONEException as e:
              raise django.core.management.base.CommandError(
                  "Could not find a functional CN or MN at the provided BaseURL. "
                  'base_url="{}" error="{}"'.format(
                      self.options["baseurl"], e.friendly_format()
                  )
              )
  
          is_cn = d1_common.type_conversions.pyxb_get_type_name(node_pyxb) == "NodeList"
  
          if is_cn:
              self.assert_is_known_node_id(
                  node_pyxb, django.conf.settings.NODE_IDENTIFIER
              )
              self._logger.info(
                  "Importing from CN: {}. filtered on MN: {}".format(
                      d1_common.xml.get_req_val(
                          self.find_node(node_pyxb, self.options["baseurl"]).identifier
                      ),
                      django.conf.settings.NODE_IDENTIFIER,
                  )
              )
              return "cn", "v2"
          else:
              self._logger.info(
                  "Importing from MN: {}".format(
                      d1_common.xml.get_req_val(node_pyxb.identifier)
                  )
              )
              return "mn", self.find_node_api_version(node_pyxb)