Example builder pattern in Python

thingy_and_its_maker.py

class ThingyMaker(object):
    def __init__(self):
        self.thingy = None
        self.widget = None

    def with_thingy(self, thingy):
        self.thingy = thingy
        return self

    def with_widget(self, widget):
        self.widget = widget
        return self

    def make_thingy(self):
        return Thingy(self.thingy, self.widget)

class Thingy(object):
    def __init__(self, thingy, widget):
        self.thingy = None
        self.widget = None