Cause dictionary with valid and user words to be cached on disk.

def _construct_user_dictionary(global_options, tool_options):
    """Cause dictionary with valid and user words to be cached on disk."""
    del global_options

    spellchecker_cache_path = tool_options.get("spellcheck_cache", None)
    valid_words_dictionary_helper.create(spellchecker_cache_path)