def find_mode(data):
    """\
    Returns the appropriate QR Code mode (an integer constant) for the
    provided `data`.

    :param bytes data: Data to check.
    :rtype: int
    """
    if data.isdigit():
        return consts.MODE_NUMERIC
    if is_alphanumeric(data):
        return consts.MODE_ALPHANUMERIC
    if is_kanji(data):
        return consts.MODE_KANJI
    return consts.MODE_BYTE