Problems with Tkinter in Python

topFrame=Frame(root)
topFrame.pack()
bottomFrame=Frame(root)
bottomFrame.pack(side=BOTTOM)

one=Label(root, text="one", bg="black", fg="white")
two=Label(root, text="Two", bg="white", fg="black")
three=Label(root, text="three", fg="purple", bg="green")
one.pack()
two.pack(fill=X)
three.pack(side=LEFT, fill=Y

button1=Button(topFrame, text="Button1", fg="red")
button2=Button(topFrame, text="Button2", fg="green")
button3=Button(topFrame, text="Button3", fg="blue")
button4=Button(bottomFrame, text="Button4", fg="purple")


button1.pack(side=LEFT)
button2.pack(side=LEFT)
button3.pack(side=LEFT)
button4.pack(side=BOTTOM)



root.mainloop()

button1=Button(topFrame, text="Button1", fg="red")