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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 disconnect(self, receiver):
 """ Disconnect a receiver from a signal. Signal and receiver must exist, otherwise an exception is thrown. :param receiver: Name of the receiver """

        if receiver not in self.receivers.keys():
            raise Exception("No receiver %s was registered" % receiver)
        self.receivers[receiver].disconnect()
        del(self.receivers[receiver])
        self.__log.debug("Receiver %s disconnected" % receiver)