def _sync_params_from_devices(self):
        """Synchronize parameters from devices to CPU. This function should be called after
        calling `update` that updates the parameters on the devices, before one can read the
        latest parameters from `self._arg_params` and `self._aux_params`.
        """
        self._exec_group.get_params(self._arg_params, self._aux_params)
        self._params_dirty = False
Synchronize parameters from devices to CPU. This function should be called after
        calling `update` that updates the parameters on the devices, before one can read the
        latest parameters from `self._arg_params` and `self._aux_params`.
        
faster_rcnn/core/module.py