def find_new_values(data, values, key):
    """Identify any new label/description values which could be added to an item.

    @param data: the contents of the painting item
    @type data: dict
    @param values: the output of either make_labels or make_descriptions
    @type values: dict
    @param key: the type of values being processed (labels or descriptions)
    @type key: string
    @return lang-value pairs for new information
    @rtype dict
    """
    new_values = {}
    for lang, value in values.iteritems():
        if lang not in data.get(key).keys():
            new_values[lang] = value['value']
    return new_values