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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 set_start_time(self, start_time):
 """ set the start time. when start time is set, drop down list will start from start time and duration will be displayed in brackets """

        start_time = start_time or dt.time()
        if isinstance(start_time, dt.time): # ensure that we operate with time
            self.start_time = dt.time(start_time.hour, start_time.minute)
        else:
            self.start_time = dt.time(start_time.time().hour, start_time.time().minute)