code: def test_demeshgrid():
      x = np.linspace(-1, 1, 10)
      t = np.linspace(0, 1, 10)
  
      _, T = np.meshgrid(x, t)
      assert (util.demeshgrid(T) == t).all()
  
      _, _, T = np.meshgrid(x, x, t)
      assert (util.demeshgrid(T) == t).all()
  
imports: import pytest
  import numpy
  import animatplot.util
label_desc: Use image node_id 2 for calling a global function with example usage: test_demeshgrid() without return types