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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 initialize(self):
 """Initialize croniter and related times"""

        if self.croniter is None:
            self.time = time.time()
            self.datetime = datetime.now(self.tz)
            self.loop_time = self.loop.time()
            self.croniter = croniter(self.spec, start_time=self.datetime)