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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 reset(self, value=None):
 """ Resets the start time of the interval to now or the specified value. """


    if value is None:
      value = time.clock()
    self.start = value
    if self.value_on_reset:
      self.value = self.value_on_reset