This is a function to take a Q object and construct a function which returns a boolean. This lets you use the exact same filter syntax that Django's managers use and apply it inside list comprehensions, or to non-persistent objects, or to objects of different types with the same attribute names.
This is, I think, a slightly cleaner implentation of what [snippet 31](/snippets/31/) is trying to do; by starting off with a dictionary containing the things we want to look for, and using a list comprehension to kill anything which comes out of the form as `None`, we can avoid some of the intermediate data structures the other snippet was using, and hopefully get better performance. This is also quite a bit more maintainable, because supporting additional options now only requires adding a new key/value pair to `qdict`.
2 snippets posted so far.