code: def get_extended_metadata(self, item_id):
          
          response = self.soap_client.call(
              'getExtendedMetadata',
              [('id', item_id)])
          return response.get('getExtendedMetadataResult', None)
docs: Get extended metadata for a media item, such as related items.
  
          Args:
              item_id (str): The item for which metadata is required.
  
          Returns:
              ~collections.OrderedDict: The item's extended metadata or None.
  
          See also:
              The Sonos `getExtendedMetadata API
              <http://musicpartners.sonos.com/node/128>`_