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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 save(self, path, key, format, data):
 """Save a newly generated thumbnail. path: path of the source image key: key of the thumbnail format: thumbnail's file extension data: thumbnail's binary data """

        thumbpath = self.get_thumbpath(path, key, format)
        fullpath = os.path.join(self.out_path, thumbpath)
        self.save_thumb(fullpath, data)
        url = self.get_url(thumbpath)
        thumb = Thumb(url, key, fullpath)
        return thumb