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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 get_url(self):
 """ Return the tus upload url. If resumability is enabled, this would try to get the url from storage if available, otherwise it would request a new upload url from the tus server. """

        if self.store_url and self.url_storage:
            key = self.fingerprinter.get_fingerprint(self.get_file_stream())
            url = self.url_storage.get_item(key)
            if not url:
                url = self.create_url()
                self.url_storage.set_item(key, url)
            return url
        else:
            return self.create_url()