def when_wordlist_is_available():
    """
        Wait for the wordlist to be available.

        This fires when the wordlist is available, which means
        ``get_word_completions()`` is able to return a non-empty set.  This
        requires the nameplate be submitted, and may also require some server
        interaction (to claim the channel and learn a channel-specific
        wordlist, e.g. for i18n language selection).

        :return: a ``Deferred`` that fires when the wordlist is available
        :rtype: Deferred[None]
        """
