def getScriptLanguageSystems(feaFile):
    """Return dictionary keyed by Unicode script code containing lists of
    (OT_SCRIPT_TAG, [OT_LANGUAGE_TAG, ...]) tuples (excluding "DFLT").
    """
    languagesByScript = collections.OrderedDict()
    for ls in [
        st
        for st in feaFile.statements
        if isinstance(st, ast.LanguageSystemStatement)
    ]:
        if ls.script == "DFLT":
            continue
        languagesByScript.setdefault(ls.script, []).append(ls.language)

    langSysMap = collections.OrderedDict()
    for script, languages in languagesByScript.items():
        sc = unicodedata.ot_tag_to_script(script)
        langSysMap.setdefault(sc, []).append((script, languages))
    return langSysMap