code: def test_subplot_polar_normalization():
      ax1 = plt.subplot(111, projection="polar")
      ax2 = plt.subplot(111, polar=True)
      ax3 = plt.subplot(111, polar=True, projection="polar")
      assert ax1 is ax2
      assert ax1 is ax3
  
      with pytest.raises(
          ValueError, match="polar=True, yet projection='3d'"
      ):
          ax2 = plt.subplot(111, polar=True, projection="3d")
  
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 16 for calling a global function with example usage: test_subplot_polar_normalization() without return types