Python Calculator

[nevets04]

Code:

def menu():
    print "---------------------------------------------------"
    print "        Welcome To Nevets04's Calculator"
    print "---------------------------------------------------"
    print "1) Addition"
    print "2) Subtraction"
    print "3) Multiplication"
    print "4) Division"
    print "5) Quit"
    return input ("Choose an operation: ")
def add(a,b):
    print a, "+", b, "=", a + b
def sub(a,b):
    print a, "-", b, "=", a - b
def mul(a,b):
    print a, "x", b, "=", a * b
def div(a,b):
    print a, "/", b, "=", a / b
loop = 1
choice = 0
while loop == 1:
    choice = menu()
    if choice == 1:
        add(input("Add this: "), input("To this: "))
    elif choice == 2:
        sub(input("Subtract this: "), input("From this: "))
    elif choice == 3:
        mul(input("Multiply this: "), input("With this: "))
    elif choice == 4:
        div(input("Divide this: "), input("By this: "))
    elif choice == 5:
        loop = 0