code: def _get_subelements(self, node):
          
          items = node.find('rdf:Alt', self.NS)
          if items is not None:
              try:
                  return items[0].text
              except IndexError:
                  return ''
  
          for xmlcontainer, container, insertfn in XMP_CONTAINERS:
              items = node.find('rdf:{}'.format(xmlcontainer), self.NS)
              if items is None:
                  continue
              result = container()
              for item in items:
                  insertfn(result, item.text)
              return result
          return ''
docs: Gather the sub-elements attached to a node
  
          Gather rdf:Bag and and rdf:Seq into set and list respectively. For
          alternate languages values, take the first language only for
          simplicity.