Unidad No.4: Practica #7: Interes anual

#Aqui insertamos el codigo
#programa que calcula el interes anual
 
#!/usr/bin/env python
#  -*- coding: utf-8 -*-
 
import sys
from Tkinter import *
import tkMessageBox
 
def interes():
 
        v1 = int(ent1.get())
        v2 = int(ent2.get())
        v3 = int(ent3.get())
        r = v1 * v2 / 100
        g=(r * v3)
        f= g + v1
        print "Cuando pasen", v3, "anos, con un interes de", v2, " usted habra generado",f , "pesos"
v = Tk()
v.title("Interes")
v.geometry("400x250")
 
vp= Frame(v)
vp.grid(column=0, row=0, padx=(50,50), pady=(10,10))
vp.columnconfigure(0, weight=1)
vp.rowconfigure(0,weight=1)
 
e1 = Label(vp, text="Pesos:")
e1.grid(row=2, column=4, padx=(20, 20), pady=(20, 20))
 
e2 = Label(vp, text="Interes:")
e2.grid(row=3, column=4, padx=(20, 20), pady=(20, 20))
 
e3 = Label(vp, text="Anos:")
e3.grid(row=4, column=4, padx=(20, 20), pady=(20, 20))
 
val1 = ""
ent1 = Entry(vp, width=12, textvariable=val1)
ent1.grid(row=2, column=5)
 
val2 = ""
ent2 = Entry(vp, width=12, textvariable=val2)
ent2.grid(row=3, column=5)
 
val3 = ""
ent3 = Entry(vp, width=12, textvariable=val3)
ent3.grid(row=4, column=5)
 
b1 = Button(vp, text="Calcular", command=interes)
b1.grid(row=5, column=5, padx=(20, 20), pady=(20, 20))
 
v.mainloop()