code: def test_hinnodemapper_manual_schema():
      """
      Tests checks on head nodes
      """
      n_batch = 2
      feature_sizes = {"t1": 1, "t2": 2}
      G, nodes_type_1, nodes_type_2 = example_hin_2(feature_sizes)
  
      # Create manual schema
      schema = G.create_graph_schema()
      HinSAGENodeGenerator(
          G,
          schema=schema,
          batch_size=n_batch,
          num_samples=[1],
          head_node_type="t1",
      ).flow(nodes_type_1)
  
imports: from stellargraph.core.graph import *
  from stellargraph.mapper import *
  import networkx
  import numpy
  import random
  import pytest
  import pandas
  import scipy.sparse
  from ..test_utils.graphs import example_graph, example_graph_random, example_hin_1, create_graph_features, repeated_features, weighted_tree
  from ..None import test_utils
label_desc: Use image node_id 22 for calling a global function with example usage: test_hinnodemapper_manual_schema() without return types