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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 _ensure_connection(self):
 """Make certain we have a valid connection and return it."""

        conn = self.connect()
        if conn.recycle and conn.recycle < time.time():
            logger.debug('Client session expired after %is. Recycling.', self._recycle)
            self.close()
            conn = self.connect()
        return conn