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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 is_time_day_valid(self, timestamp):
 """Check if it is within start time and end time of the DateRange :param timestamp: time to check :type timestamp: int :return: True if t in range, False otherwise :rtype: bool """

        (start_time, end_time) = self.get_start_and_end_time(timestamp)
        return start_time <= timestamp <= end_time