Write a Python program to calculate the sum of two given integers, but only if both of them are even.
num1 = 6
num2 = 8
def sum_of_two_ints(a,b): 
    if (a % 2 == 0 and b % 2 == 0): 
        return a+b 
    else: 
        return "Wrong input"

print(sum_of_two_ints(num1,num2))