code: def check_pause(self):
          
  
          # todo task_runner vs model
  
          pause_time = 0.0
          sleep_time = 0.1
          if self.model.tasks_paused:
              while self.model.tasks_paused:
                  sleep(pause_time)
                  pause_time += sleep_time
          return pause_time
docs: Call at regular intervals within long running tasks to add pause breakpoints.
          :return: time that the task was paused for, always 0.0 if it didn't pause
          :rtype: float