code: def test_draw_shell_nlist():
      try:
          nlist = [
              list(range(4)),
              list(range(4, 10)),
              list(range(10, 14)),
          ]
          nx.draw_shell(barbell, nlist=nlist)
          plt.savefig("test.ps")
      finally:
          try:
              os.unlink("test.ps")
          except OSError:
              pass
  
imports: import itertools
  import os
  import warnings
  import pytest
  import networkx
label_desc: Use image node_id 2 for calling a global function with example usage: test_draw_shell_nlist() without return types