<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def load_target_vocab(folder: str) -> Vocab: """ Loads target vocabulary from folder. :param folder: Source folder. :return: Target vocabulary """

    return vocab_from_json(os.path.join(folder, C.VOCAB_TRG_NAME % 0))