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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def description(tag):
 """ Gets a list of descriptions given the tag. :param str tag: (hyphen-separated) tag. :return: list of string descriptions. The return list can be empty. """

        tag_object = Tag(tag)
        results = []
        results.extend(tag_object.descriptions)
        subtags = tag_object.subtags
        for subtag in subtags:
            results += subtag.description

        return results