code: def test_when_plot_does_not_raise_exception():
      plot(nx.DiGraph([("X", "Y"), ("Y", "Z")]))
  
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 1 for calling a global function with example usage: test_when_plot_does_not_raise_exception() without return types