code: def forward(self, x, edge_index):
      return self.gnn(x, edge_index)
  
file_path: pytorch_geometric/examples/pytorch_lightning/graph_sage.py
imports: import os.path
  import pytorch_lightning
  import torch
  import torch.nn.functional
  from torch.nn import BatchNorm1d
  from torchmetrics import Accuracy
  from torch_geometric.data.lightning import LightningNodeData
  from torch_geometric.datasets import Reddit
  from torch_geometric.nn import GraphSAGE
label_desc: Use image node_id 2 for calling the Model obj's underlying member method code with example usage: obj.forward(x, edge_index) and returns: self