def METHOD_NAME() -> str:
    """
    Return tmuxp workspace directory.
    ``TMUXP_CONFIGDIR`` environmental variable has precedence if set. We also
    evaluate XDG default directory from XDG_CONFIG_HOME environmental variable
    if set or its default. Then the old default ~/.tmuxp is returned for
    compatibility.
    Returns
    -------
    str :
        absolute path to tmuxp config directory
    """
    paths = []
    if "TMUXP_CONFIGDIR" in os.environ:
        paths.append(os.environ["TMUXP_CONFIGDIR"])
    if "XDG_CONFIG_HOME" in os.environ:
        paths.append(os.path.join(os.environ["XDG_CONFIG_HOME"], "tmuxp"))
    else:
        paths.append("~/.config/tmuxp/")
    paths.append("~/.tmuxp")
    for path in paths:
        path = os.path.expanduser(path)
        if os.path.isdir(path):
            return path
    # Return last path as default if none of the previous ones matched
    return path