class_docstr: Implement of APPNP
class_docstr_tok: ["Implement","of","APPNP"]
code: def forward(self, graph_wrapper, feature, phase):
      if phase == "train":
          edge_dropout = self.edge_dropout
      else:
          edge_dropout = 0
  
      for i in range(self.num_layers):
          feature = L.dropout(
              feature,
              self.dropout,
              dropout_implementation="upscale_in_train",
          )
          feature = L.fc(
              feature, self.hidden_size, act="relu", name="lin%s" % i
          )
  
      feature = L.dropout(
          feature,
          self.dropout,
          dropout_implementation="upscale_in_train",
      )
  
      feature = L.fc(feature, self.num_class, act=None, name="output")
  
      feature = conv.appnp(
          graph_wrapper,
          feature=feature,
          edge_dropout=edge_dropout,
          alpha=self.alpha,
          k_hop=self.k_hop,
      )
      return feature
  
imports: import pgl
  import paddle.fluid.layers
  import pgl.layers.conv
label_desc: Use image node_id 2 for calling the APPNP obj's underlying member method code with example usage: obj.forward(graph_wrapper, feature, phase) and returns: feature