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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 wait(self, timeout=None):
 """ An implementation of the wait method which doesn't involve polling but instead utilizes a "real" synchronization scheme. """

        import threading

        if self._state!=self.PENDING:
            return

        e = threading.Event()
        self.addCallback(lambda v: e.set())
        self.addErrback(lambda r: e.set())
        e.wait(timeout)