code: def values(self, *keys):
          
          if keys:
              d = []
              for key in keys:
                  try:
                      i = self.index(key)
                  except KeyError:
                      d.append(None)
                  else:
                      d.append(self[i])
              return d
          return list(self)
docs: Return the values of the record, optionally filtering to
          include only certain values by index or key.
  
          :param keys: indexes or keys of the items to include; if none
                       are provided, all values will be included
          :return: list of values