class_docstr: Implementation of GIN + SAGPool.
      
class_docstr_tok: ["Implementation","of","GIN","+","SAGPool","."]
docstr: SAGPool Forward
docstr_tok: ["SAGPool","Forward"]
code: def forward(self, graph):
      """
      SAGPool Forward
      """
      x = graph.node_feat["attr"]
      g = graph
      x = F.relu(self.conv1(g, x))
      x, _, g = self.pool1(g, x)
      x = F.relu(self.conv2(g, x))
      x, _, g = self.pool2(g, x)
      x = F.relu(self.conv3(g, x))
      x = segment_max(x, g.graph_node_id)
      x = self.out_layer(x)
      return x
  
file_path: PGL/examples/sag_pool/model.py
imports: import os
  import sys
  import time
  import argparse
  import numpy
  import paddle
  import paddle.nn
  import paddle.nn.functional
  import pgl
  from pgl.nn import SAGPool, GINConv
  from pgl.math import segment_max
label_desc: Use image node_id 2 for calling the GINModel obj's underlying member method code with example usage: obj.forward(graph) and returns: x