def __init__(self, calltime, slot):
        self.calltime = calltime
        self.slot = slot
        self.delay = np.random.normal(loc=0, scale=2.5,size=None)
        self.arrivalTime = self.slot + dt.timedelta(minutes=self.delay)
        self.scanWaitingTime = self.arrivalTime - self.slot
        self.scanStartTime =
        self.scanEndTime =

self.scanStartTime = if self.arrivalTime > slot:
                        return arrivalTime
                     else:
                        return slot