__author__ = 'dsteil'
import Tkinter
import Tkinter.messagebox
from Tkinter import *

class MultiWindowExample:
    def __init__(self):
        self.__mainWindow = Tkinter.Tk()

        newButton = Tkinter.Button(self.__mainWindow, text="T")
        newButton.config(command=lambda button=newButton: self.OnButtonClick(button))
        newButton.grid(row=0, column=0)

        self.__mainWindow.mainloop()

    def OnButtonClick(self,button):
        newGUI = MultiWindowExample()

gui_Example = MultiWindowExample()