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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_valid(self, timestamp):
 """Check if time is valid for this Timerange If sec_from_morning is not provided, get the value. :param timestamp: time to check :type timestamp: int :return: True if time is valid (in interval), False otherwise :rtype: bool """

        sec_from_morning = get_sec_from_morning(timestamp)
        return (self.is_valid and
                self.hstart * 3600 + self.mstart * 60 <=
                sec_from_morning <=
                self.hend * 3600 + self.mend * 60)