def get_xyz_coords(illuminant, observer):
 illuminant = illuminant.upper()
 try:
  return illuminants[illuminant][observer]
 except KeyError:
  raise ValueError("Unknown illuminant/observer combination        ('{0}', '{1}')".format(illuminant, observer))

def get_xyz_coords ( illuminant , observer ) : illuminant = illuminant . upper ( ) try : return illuminants [ illuminant ] [ observer ] except KeyError : raise ValueError ( "Unknown illuminant/observer combination        ('{0}', '{1}')" . format ( illuminant , observer ) )
get the xyz coordinates of the given illuminant and observer [1]_ .