code: def test_gca():
      # plt.gca() returns an existing axes, unless there were no axes.
      plt.figure()
      ax = plt.gca()
      ax1 = plt.gca()
      assert ax is not None
      assert ax1 is ax
      plt.close()
  
imports: import difflib
  import numpy
  import sys
  from pathlib import Path
  import pytest
  import matplotlib
  from matplotlib.testing import subprocess_run_for_testing
  from matplotlib import pyplot
label_desc: Use image node_id 14 for calling a global function with example usage: test_gca() without return types