code: def graph_pooling(gw, node_feat, pool_type):
      """Implementation of graph pooling
  
      This is an implementation of graph pooling
  
      Args:
          gw: Graph wrapper object (:code:`StaticGraphWrapper` or :code:`GraphWrapper`)
  
          node_feat: A tensor with shape (num_nodes, feature_size).
  
          pool_type: The type of pooling ("sum", "average" , "min")
  
      Return:
          A tensor with shape (num_graph, hidden_size)
      """
      graph_feat = op.nested_lod_reset(node_feat, gw.graph_lod)
      graph_feat = L.sequence_pool(graph_feat, pool_type)
      return graph_feat
  
file_path: PGL/legacy/pgl/layers/graph_op.py
imports: import paddle.fluid
  import paddle.fluid.layers
  from pgl import graph_wrapper
  from pgl.utils import paddle_helper
  from pgl.utils import op
label_desc: Use image node_id 1 for calling a global function with example usage: graph_pooling(gw, node_feat, pool_type) and returns: graph_feat