def time_this(original_function):
    def new_function(*args, **kwargs):
        import datetime
        before = datetime.datetime.now()
        x = original_function(*args, **kwargs)
        after = datetime.datetime.now()
        print("Elapsed Time = {0}".format(after - before))
        return x

    return new_function


@time_this
def func_a(stuff):
    import time
    time.sleep(3)
    print("ai")


func_a(1)