code: def test_negative():
      f = 255 * np.random.random((228, 228))
      f = f.astype(np.uint8)
      h, w = 12, 6
      t = f[:h, :w]
      matches = mh.find(f, t)
      coords = np.array(np.where(matches))
      for y, x in zip(*coords):
          if y < 0 or x < 0:
              continue
          assert np.all(f[y : y + h, x : x + w] == t)
  
imports: import numpy
  import mahotas
label_desc: Use image node_id 2 for calling a global function with example usage: test_negative() without return types