code: def __init__(self, in_size, hidden_size, out_size):
      super().__init__()
      self.layers = nn.ModuleList()
      # Two-layer GraphSAGE-gcn.
      self.layers.append(dglnn.SAGEConv(in_size, hidden_size, "gcn"))
      self.layers.append(dglnn.SAGEConv(hidden_size, out_size, "gcn"))
      self.dropout = nn.Dropout(0.5)
  
file_path: dgl/examples/core/graphsage/node_classification.py
imports: import argparse
  import time
  import dgl.nn
  import torch
  import torch.nn
  import torch.nn.functional
  from dgl import AddSelfLoop
  from dgl.data import CiteseerGraphDataset, CoraGraphDataset, PubmedGraphDataset
label_desc: Use image node_id 1 to create a new SAGE object from inherited base classes: nn with example: obj = SAGE(in_size, hidden_size, out_size)