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