I have an important message for web spider operators: our generosityis not unlimited. In fact, it's probably running out.

There are a lot of web spiders out there, and many of these spidersdon't seem to be offering anything for free to the public. When youcrawl to build a private index, you're building a business in part off our resources, which you are using for free, and there is verylittle in this for us. To put it plainly, such spider

Python calls the __len__ method on your objects to implement len() , and in a few other situations (for example, as one way ofiterating through the elements of a sequence-likeobject). Surprisingly, there's an under-documented restriction on whatyour __len__ can return: objects can't be larger than sys.maxint .

In fact, it's stricter than that: your __len__ method must returna literal integer. You