code: def test_plot_adjacency_matrix():
      causal_graph = pd.DataFrame(
          np.array([[0, 1, 0], [0, 0, 1], [0, 0, 0]]),
          columns=["X", "Y", "Z"],
          index=["X", "Y", "Z"],
      )
  
      # Check if calling the method causes some import or runtime errors
      plot_adjacency_matrix(causal_graph, is_directed=True)
  
file_path: dowhy/tests/utils/test_plotting.py
imports: import networkx
  import numpy
  import pandas
  import pytest
  from _pytest.python_api import approx
  from dowhy.utils import plot, plot_adjacency_matrix
  from dowhy.utils.networkx_plotting import plot_causal_graph_networkx
  from dowhy.utils.plotting import _calc_arrow_width, bar_plot
label_desc: Use image node_id 2 for calling a global function with example usage: test_plot_adjacency_matrix() without return types