code: def test_overflow():
      """[watershed regression]: Try to force overflow on the output
  
      This was reported as issue #41 on github:
  
      https://github.com/luispedro/mahotas/issues/41
      """
      f = np.random.random((128, 64))
      f *= 255
      f = f.astype(np.uint8)
      for max_n in [127, 240, 280]:
          markers = np.zeros(f.shape, np.int_)
          for i in range(max_n):
              while True:
                  a = np.random.randint(f.shape[0])
                  b = np.random.randint(f.shape[1])
                  if markers[a, b] == 0:
                      markers[a, b] = i + 1
                      break
  
          r = mh.cwatershed(f, markers)
          assert markers.max() == max_n
          assert r.max() == max_n
  
file_path: mahotas/mahotas/tests/test_watershed.py
imports: import numpy
  import mahotas
  import mahotas
  import sys
  import pytest
label_desc: Use image node_id 6 for calling a global function with example usage: test_overflow() without return types