Try to read data from configuration paths ($HOME/_SETTINGS_PATH,
    /etc/_SETTINGS_PATH).

def _read_from_paths():
    """
    Try to read data from configuration paths ($HOME/_SETTINGS_PATH,
    /etc/_SETTINGS_PATH).
    """
    home = os.environ.get("HOME", "")
    home_path = os.path.join(home, _SETTINGS_PATH)
    etc_path = os.path.join("/etc", _SETTINGS_PATH)
    env_path = os.environ.get("SETTINGS_PATH", "")

    read_path = None
    if env_path and os.path.exists(env_path):
        read_path = env_path
    elif home and os.path.exists(home_path):
        read_path = home_path
    elif os.path.exists(etc_path):
        read_path = etc_path

    if not read_path:
        return "{}"

    with open(read_path) as f:
        return f.read()