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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 count(self, until=None):
 """ Returns the total number of jobs that are scheduled for all queues. This function accepts datetime, timedelta instances as well as integers representing epoch values. """


        until = rationalize_until(until)
        return self.connection.zcount(self.scheduled_jobs_key, 0, until)