def update(self):
        """Update parameters according to the installed optimizer and the gradients computed
        in the previous forward-backward batch.
        """
        assert self.binded and self.params_initialized and self.optimizer_initialized

        self._params_dirty = True
        if self._update_on_kvstore:
            try:
                _update_params_on_kvstore(self._exec_group.param_arrays,
                                          self._exec_group.grad_arrays,
                                          self._kvstore)
            except:
                _update_params_on_kvstore(self._exec_group.param_arrays,
                                          self._exec_group.grad_arrays,
                                          self._kvstore, param_names=self._exec_group.param_names)
        else:
            _update_params(self._exec_group.param_arrays,
                           self._exec_group.grad_arrays,
                           updater=self._updater,
                           num_device=len(self._context),
                           kvstore=self._kvstore)
Update parameters according to the installed optimizer and the gradients computed
        in the previous forward-backward batch.
        
faster_rcnn/core/module.py