docs: def of_pyobj(self, pyobj):
          """Use default hash method to return hash value of a piece of Python
          picklable object.
          """
          m = self.hash_algo()
          m.update(pickle.dumps(pyobj, protocol=self.pk_protocol))
          if self.return_int:
              return int(m.hexdigest(), 16)
          else:
              return m.hexdigest()