code: def gcn_msg(edge):
      msg = edge.src["h"] * edge.src["norm"]
      return {"m": msg}
  
file_path: dgl/examples/mxnet/gcn/gcn_mp.py
imports: import mxnet
  from mxnet import gluon
label_desc: Use image node_id 1 for calling a global function with example usage: gcn_msg(edge) and returns: dict