code: def check_activation(self, contacts):
          
          now = time.time()
          was_is_in_effect = self.is_in_effect
          self.is_in_effect = (self.start_time <= now <= self.end_time)
  
          # Raise a log entry when we get in the downtime
          if not was_is_in_effect and self.is_in_effect:
              self.enter(contacts)
  
          # Same for exit purpose
          if was_is_in_effect and not self.is_in_effect:
              self.exit(contacts)
docs: Enter or exit downtime if necessary
  
          :return: None