code: def pause_tasks(self):
          '''暂停所有下载任务'''
          if self.first_run:
              return
          for row in self.liststore:
              self.pause_task(row, scan=Falsef pause_tasks(self):
          '''暂停所有下载任务'''
          if self.first_run:
              return
          for row in self.liststore:
              self.pause_task(row, scan=False)
docs: 暂停所有下载任务