new_contents: import mapnik
  from nose.tools import *
  
  def test_grayscale_conversion():
      im = mapnik.Image(2,2)
      im.background = mapnik.Color('white')
      im.set_grayscale_to_alpha()
      pixel = im.get_pixel(0,0)
      eq_((pixel >> 24) & 0xff,255);
  
  if __name__ == "__main__":
      [eval(run)() for run in dir() if 'test_' in run]
  
subject: add grayscale conversion test - refs #1454