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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 backoff_generator(self):
 """Generate a series of integers used for the length of the sleep between retries. It produces after exhausting the list, it repeats the last value from the list forever. This generator will never raise the StopIteration exception."""

        for x in self.config.backoff_delays:
            yield x
        while True:
            yield self.config.backoff_delays[-1]