code: def test_smoke():
      f = np.random.random((512, 1024))
      se = np.ones((2, 2))
      ff = mean_filter(f, se)
      for _ in range(128):
          a = np.random.randint(1, f.shape[0] - 1)
          b = np.random.randint(1, f.shape[1] - 1)
          assert np.allclose(
              ff[a, b], np.mean(f[a - 1 : a + 1, b - 1 : b + 1])
          )
  
imports: import numpy
  import mahotas
  from mahotas.convolve import mean_filter
label_desc: Use image node_id 1 for calling a global function with example usage: test_smoke() without return types