code: def _run(self):
          
          try:
              if self.run():
                  broadcaster.success(self)
              else:
                  broadcaster.failure(self)
          except StandardError:
              import traceback
              traceback.print_exc()
              self._stop()
              raise
          except Exception:
              self._stop()
              raise
          return True
docs: Calls self.run() and wraps for errors.