def tell_size(obj, word, suffix="s"):
    """Useful when you want to write a message to the user.

    :param obj: The object being described.
    :type obj: Anything that works with the len() function.
    :param word: Word to use to describe the object.
    :type word: ``str``
    :param suffix: What to append to the word if plural.
    :type suffix: ``str``

    :return: The length, followed by the possibly pluralized word.
    :rtype: ``str``
    """
    if len(obj) == 1:
        return "1 {}".format(word)
    else:
        return "{} {}{}".format(len(obj), word, suffix)