def METHOD_NAME():
    """Return a generator for all formatter classes."""
    # NB: this returns formatter classes, not info like get_all_lexers().
    for info in FORMATTERS.values():
        if info[1] not in _formatter_cache:
            _load_formatters(info[0])
        yield _formatter_cache[info[1]]
    for _, formatter in find_plugin_formatters():
        yield formatter