Minor nitpick, but could we use 'class_' instead of 'klass'? >From the 'Pythonic guidelines' in PEP 8:
- If your public attribute name collides with a reserved keyword, append a single trailing underscore to your attribute name. This is preferable to an abbreviation or corrupted spelling. E.g. "class_" is preferable to "cls" or "klass". Not a big deal, but I thought it was worth asking for. MWM
