def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def stroke_rectangle(self, x, y, w, h):
		self.line(x,y,w,True)
		self.line(x,y+h-1,w,True)
		self.line(x,y,h,False)
		self.line(x+w-1,y,h,False)