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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 hydrate(self, broker=None):
 """ Loads a Broker from a previously saved one. A Broker is created if one isn't provided. """

        broker = broker or dr.Broker()
        for path in glob(os.path.join(self.meta_data, "*")):
            try:
                with open(path) as f:
                    doc = ser.load(f)
                    res = self._hydrate_one(doc)
                    comp, results, exec_time, ser_time = res
                    if results:
                        broker[comp] = results
                        broker.exec_times[comp] = exec_time + ser_time
            except Exception as ex:
                log.warning(ex)
        return broker