code: def _send_notification(self, handle, payload):
          
  
          self.bable.notify(
              connection_handle=self._connection_handle,
              attribute_handle=handle,
              value=payload
          )
docs: Send a notification over BLE
          It is executed in the baBLE working thread: should not be blocking.
  
          Args:
              handle (int): The handle to notify on
              payload (bytearray): The value to notify