Update classtree.py

[(<type 'object'>, ()),
 [(<class 'turtle.TNavigator'>, (<type 'object'>,)),
  (<class 'turtle.TPen'>, (<type 'object'>,)),
  [(<class 'turtle.RawTurtle'>,
    (<class 'turtle.TPen'>, <class 'turtle.TNavigator'>)),
   [(<class 'turtle.Turtle'>, (<class 'turtle.RawTurtle'>,))]]]]
object()
TNavigator(object)
TPen(object)
RawTurtle(TPen, TNavigator)
Turtle(RawTurtle)