docs: def unwrap(self, value, session=None):
          ''' Expects a list of dictionaries with ``k`` and ``v`` set to the
              keys and values that will be unwrapped into the output python
              dictionary should have.  Validates the input and then constructs the
              dictionary from the list.
          '''
          self.validate_unwrap(value)
          ret = {}
          for value_dict in value:
              k = value_dict['k']
              v = value_dict['v']
              ret[self.key_type.unwrap(k, session=session)] = self.value_type.unwrap(v, session=session)
          return ret