code: def forward_layer(self, layer, graph, x, norm=None, state=None):
      raise NotImplementedError
  
file_path: PGL/apps/GNNAutoScale/gnn_models/base_model.py
imports: import os
  import sys
  import numpy
  import paddle
  from pgl.utils.stream_pool import StreamPool, async_write
  from history import History
  from utils import process_batch_data, check_device
label_desc: Use image node_id 8 for calling the ScalableGNN obj's underlying member method code with example usage: obj.forward_layer(layer, graph, x, norm, state) without return types