Simple calculator program in python

 def add(x,y):

    return x+y

def subtract(x,y):

    return x-y

def multiply(x,y):

    return x*y

def divide(x,y):

    return x/y

print("___Simple Calculator___")

print("1. Addition")

print("2. Subtraction")

print("3. Multiplication")

print("4. Division")

choice = input("Enter your choice 1 or 2 or  3 or 4 ")

if choice in ('1','2','3','4'):

        a=float(input("Enter first number "))

        b=float(input("Enter second number "))

        if choice == '1':

            print(a,"+",b,"=",add(a,b))

        elif choice == '2':

            print(a,"-",b,"=",subtract(a,b))

        elif choice == '3':

            print(a,"*",b,"=",multiply(a,b))

        elif choice == '4':

            print(a,"/",b,"=",divide(a,b))

else:

        print("Invalid entry")