from Tkinter import *
class MyDialog:
def __init__(self, parent):
top = self.top = Toplevel(parent)
Label(top, text="Value").pack()
self.e = Entry(top)
self.e.pack(padx=5)
b = Button(top, text="OK", command=self.ok)
b.pack(pady=5)
def ok(self):
print "value is", self.e.get()
self.top.destroy()
root = Tk()
d = MyDialog(root)
root.wait_window(d.top)