code: def test_init(barbell):
      generator = AdjacencyPowerGenerator(barbell, num_powers=5)
      num_nodes = len(barbell.nodes())
  
      assert generator.num_powers == 5
      assert generator.Aadj_T.shape == (num_nodes, num_nodes)
      assert generator.transition_matrix_T.shape == (
          num_nodes,
          num_nodes,
      )
  
file_path: stellargraph/tests/mapper/test_adjacency_generators.py
imports: from stellargraph.core.utils import normalize_adj
  from stellargraph.mapper.adjacency_generators import AdjacencyPowerGenerator
  from ..test_utils.graphs import barbell
  import tensorflow
  import numpy
  import pytest
label_desc: Use image node_id 1 for calling a global function with example usage: test_init(barbell) without return types