from functools import wraps

def cache(func):

    data = {}

    @wraps(func)

    def wrapper(*args):

        if args in data:

            print "in cache"

            return data[args]

        else:

            print "not in cache"

            res = func(*args)

            data[args] = res

            return res

    return wrapper

@cache

def post_data(args):

    return args

post_data(123)    # not in cache

post_data(123)    # in cache

post_data(1235)    # not in cache