What is the output when the following code executes?

def mystery(a, b):
    a = a + 1
    b = b - a
    print(a, b)

def main():
    a = 6
    b = 2
    mystery(a, b)
    print(a, b)
    a = a * 3
    b = b + a
    mystery(b, a)
    print(a, b)
main()