memoize def func print calculating return func calculating func calcul

>>> @memoize
def func(a, b):
    print "calculating %s + %s" % (a, b)
    return a + b

>>> func(1, 5)
calculating 1 + 5
<<< 6

>>> func(2, 5)
calculating 2 + 5
<<< 7

>>> func(2, 5)
<<< 7