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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 close(self):
 """ Closes the connection to the database for this connection. :return <bool> closed """

        for pool in self.__pool.values():
            while not pool.empty():
                conn = pool.get_nowait()
                try:
                    self._close(conn)
                except Exception:
                    pass

        # reset the pool size after closing all connections
        self.__poolSize.clear()