class Tokidate(object):
    def settoki(self, value):
        print "Set!", value
    def gettoki(self):
        print "Get!"
    toki = property(gettoki, settoki)

class BTClass(type(Tokidate)):
    def __setattr__(self, attr, value):
        if attr == 'toki':
            print "Set class"
        else:
            type(Tokidate).__setattr__(self, attr, value)
Tokidate.__bases__ = (BTClass, object)