noDecorators.py

class Implementation(object):
    
    def __init__(self, tag):
        self._tag = tag
        self._instance = None
            
    def __getattr__(self, attr):
        attr = "_%s_%s" % (self._tag, attr)
        return getattr(self._instance, attr)
        
    def __get__(self, instance, obj):
        self._instance = instance
        return self
    
    
class BaseContour(object):

    def aMethod(self, point):
        return "BaseContour aMethod", self, point


class BetaContour(BaseContour):

    beta = Implementation("beta")

    def _beta_aMethod(self, point):
        return "BetaContour aMethod", self, point

    def _beta_moreMethods(self, foo):
        return "BetaContour moreMethods", self, foo


class Contour(BetaContour):

    roboFont = Implementation("roboFont")

    def _roboFont_aMethod(self, point, test):
        return "Contour aMethod", self, point, test

    def _beta_testing(self, someThing):
        return "Contour testing", self, someThing

c = Contour()
print c.aMethod("a")
print c.roboFont.aMethod("a", "b")
print c.beta.moreMethods("bar")
print c.beta.testing("m")