code: def get_all(self):
          '''Return an iterator of name-value pairs.'''
          for name, values in self._map.items():
              for value in values:
                  yield (name, valuef get_all(self):
          '''Return an iterator of name-value pairs.'''
          for name, values in self._map.items():
              for value in values:
                  yield (name, value)
docs: Return an iterator of name-value pairs.