memento decorator applied on fibonacci

memento_fib.py

class Memento :
	__mem__ = {}
	def __init__(self, f) :
		self.f = f

	def __call__(self, arg) :
		if arg not in self.__mem__ :
			self.__mem__[arg] = self.f(arg)
		return self.__mem__[arg]

def fib1( n ) :
	if n <= 1 :
		return 1
	return fib1(n-1) + fib1(n-2)

@Memento
def fib2( n ) :
	if n <= 1 :
		return 1
	return fib2(n-1) + fib2(n-2)

print 'Computing fib without memento ....', fib1(35)
print 'Computing fib wth memento ....', fib2(100)