code: def get_ms_item(xml, service, parent_id):
      
      cls = MS_TYPE_TO_CLASS.get(xml.findtext(ns_tag('ms', 'itemType')))
      out = cls.from_xml(xml, service, parent_id)
      return out
docs: Return the music service item that corresponds to xml.
  
      The class is identified by getting the type from the 'itemType' tag