code: def setlist(self, key, new_list):
          # type: (Hashable, List[Any]) -> None
          
          dict.__setitem__(self, key, list(new_list))
docs: Remove the old values for a key and add new ones.  Note that the list
          you pass the values in will be shallow-copied before it is inserted in
          the dictionary.
          >>> d = MultiValueDict()
          >>> d.setlist('foo', ['1', '2'])
          >>> d['foo']
          '1'
          >>> d.getlist('foo')
          ['1', '2']
          :param key: The key for which the values are set.
          :param new_list: An iterable with the new values for the key.  Old values
                           are removed first.