code: def white_point(illuminant, observer=observers.cie_1931_2()):
      
      values = spectrum_to_xyz100(illuminant, observer)
      # normalize for relative luminance, Y=100
      values /= values[1]
      values *= 100
      return values
docs: From <https://en.wikipedia.org/wiki/White_point>:
      The white point of an illuminant is the chromaticity of a white object
      under the illuminant.