code: def forward(self, users, items):
      users_emb = self.embedding_user.weight
      items_emb = self.embedding_item.weight
      all_users, all_items = self.lightgcn(
          self.Graph, users_emb, items_emb
      )
      users_emb = paddle.index_select(all_users, users)
      items_emb = paddle.index_select(all_items, items)
      # users_emb = paddle.to_tensor(all_users.numpy()[users.numpy()])
      # items_emb = paddle.to_tensor(all_items.numpy()[items.numpy()])
      inner_pro = paddle.multiply(users_emb, items_emb)
      gamma = paddle.sum(inner_pro, axis=1)
      return gamma
  
imports: import paddle
  import paddle.nn
  from dataloader import BasicDataset
  import numpy
  import paddle
  import paddle.nn
  import paddle.nn.functional
  import pgl
  from pgl.nn import functional
  from tqdm import tqdm
label_desc: Use image node_id 5 for calling the LightGCN obj's underlying member method code with example usage: obj.forward(users, items) and returns: gamma