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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_temp_url_key(self, cached=True):
 """ Returns the current TempURL key, or None if it has not been set. By default the value returned is cached. To force an API call to get the current value on the server, pass `cached=False`. """

        meta = self._cached_temp_url_key
        if not cached or not meta:
            key = "temp_url_key"
            meta = self.get_account_metadata().get(key)
            self._cached_temp_url_key = meta
        return meta