simplecalc.py

import Tkinter
import tkMessageBox

def dosquareroot() :
    respond = float(number_input.get())
    ans = respond**(float(1)/2)
    tkMessageBox.showinfo('Answer' ,ans)

def dosquare() :
    respond = float(number_input.get())
    ans = respond**2
    tkMessageBox.showinfo('Answer' ,ans)

aimyon = Tkinter.Tk()

number_input = Tkinter.Entry(aimyon)
number_input.pack()

button1 = Tkinter.Button(aimyon, text="Square Root", command=dosquareroot)
button1.pack()

button2 = Tkinter.Button(aimyon, text="Square", command=dosquare)
button2.pack()

aimyon.mainloop()