Simple decorator to add loading and saving to a function

simple_load_save_decorator.py

from functools import wraps
import pickle
import traceback
import os

print("THIS IS ON GITHUB AT:")
print("https://gist.github.com/jmetz/93a7bee657efc1826add676ae7f68d3b/")

def save_result(func,
        loader=lambda fname: pickle.load(open(fname, "rb")),
        saver=lambda obj, fname: pickle.dump(obj, open(fname, "wb")),
        savekey="filename",
        ):
    @wraps(func)
    def wrapper(*args, **kwargs):
        if savekey in kwargs:
            fname = kwargs.pop(savekey)
        else:
            raise TypeError("This function has been decorated as using `save_result`; you must specify the additional keyword argument %s" % savekey)
        if os.path.isfile(fname):
            result = loader(fname)
        else:
            result = func(*args, **kwargs)
            saver(result, fname)
        return result
    return wrapper



@save_result
def should_not_work(a,b):
    print("RUNNING should_not_work")
    return a + b

@save_result
def should_work(a,b):
    print("RUNNING should_work")
    return a + b

if __name__ == '__main__':
    try:
        should_not_work(10,20)
    except:
        print("Good :) That wasn't supposed to work")
        print("Error anyway:")
        traceback.print_exc()
        print("REMEMBER THAT WAS FINE / EXPECTED")

    try:
        print(should_work(100,100, filename="testfile.pkl"))
        print(should_work(100,100, filename="testfile.pkl"))
        print(should_work(100,100, filename="testfile.pkl"))
    except:
        print("Damn, that should have worked")
        traceback.print_exc()