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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 tick(self):
 """Decay the current rate according to the elapsed time"""


        instant_rate = float(self.value) / float(self.tick_interval)

        with self.lock:
            if self.initialized:
                self.rate += (self.alpha * (instant_rate - self.rate))
            else:
                self.initialized = True
                self.rate = instant_rate

            self.value = 0