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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 time_conflict(self, schedule):
 """Internal use. Determines when the given time range conflicts with the set of excluded time ranges. """

        if is_nil(schedule):
            return True
        for timerange in self._excluded_times:
            if timerange.conflicts_with(schedule):
                return False
        return True