code: def get_next_asset(self):
          
          try:
              next_object = next(self)
          except StopIteration:
              raise IllegalState('no more elements available in this list')
          except Exception:  # Need to specify exceptions here!
              raise OperationFailed()
          else:
              return next_object
docs: Gets the next Asset in this list.
  
          return: (osid.repository.Asset) - the next Asset in this list.
                  The has_next() method should be used to test that a next
                  Asset is available before calling this method.
          raise:  IllegalState - no more elements available in this list
          raise:  OperationFailed - unable to complete request
          compliance: mandatory - This method must be implemented.