Tkinter Gui

Question

我想创建一个非常简单的GUI。只需一个按钮。 实际上，我试图复制此代码https://pythonprogramming.net/tkinter-python-3-tutorial-adding-buttons/

但是，我使用Python 2.7与使用Python 3.x的文章不同 在Python 2.7中运行时相同的代码不显示退出按钮，在视频中显示退出按钮。

这是我的代码

from Tkinter import *

class Window(Frame):

    def __init__(self, master = None):
        Frame.__init__(self, master)
        self.master = master
        self.init_window()


    def init_window(self):

        # changing the title of our master widget
        self.master.title("Gui")

        # allowing the widget to take the full space of the root window
        self.pack()

        # creating a button instance
        button = Button(self , text = 'quit')

        # placing the button on my window
        button.place(x=0, y=0)


if __name__ == '__main__':

    root = Tk()

    #size of the window
    root.geometry("400x300")

    app = Window(root)
    root.mainloop()

这是教程中的代码

from tkinter import *

class Window(Frame):

    def __init__(self, master=None):
        Frame.__init__(self, master)
        self.master = master
        self.init_window()

    #Creation of init_window
    def init_window(self):

        # changing the title of our master widget
        self.master.title("GUI")

        # allowing the widget to take the full space of the root window
        self.pack(fill=BOTH, expand=1)

        # creating a button instance
        quitButton = Button(self, text="Quit")

        # placing the button on my window
        quitButton.place(x=0, y=0)

root = Tk()

#size of the window
root.geometry("400x300")

app = Window(root)
root.mainloop()

有人可以解释行为上的差异吗？