shazow/urllib3 — pull request #175 by bboe (2013-04-27 02:40:03+00:00)
Title: Add RequestError subclass to PoolError.

The former PoolError `__reduce__` method was broken as it assumed the `url` attribute was set, when in fact it was not.

As per issue #174, this commit creates a `RequestError` subclass of `PoolError` and makes `MaxRetryError` and TimeoutError` a subclass of `RequestError`.