code: def test_APPNP_save_load(tmpdir, sparse):
      G, _ = create_graph_features()
      generator = FullBatchNodeGenerator(G, sparse=sparse)
      appnp = APPNP([2, 3], generator, ["relu", "relu"])
      test_utils.model_save_load(tmpdir, appnp)
  
file_path: stellargraph/tests/layer/test_appnp.py
imports: from stellargraph.layer.appnp import *
  from stellargraph.mapper import FullBatchNodeGenerator, FullBatchLinkGenerator
  from stellargraph import StellarGraph
  from stellargraph.core.utils import GCN_Aadj_feats_op
  import networkx
  import pandas
  import numpy
  from tensorflow import keras
  import pytest
  from ..test_utils.graphs import create_graph_features
  from ..None import test_utils
label_desc: Use image node_id 9 for calling a global function with example usage: test_APPNP_save_load(tmpdir, sparse) without return types