The urllib2 docs indicate that HTTPError is a subclass of URLError and that URLError has an attribute of 'reason', but HTTPError does not have this attribute. The docs should be updated to reflect this deviance.

It appears the Python 3.2 docs no longer include documentation for URLError

Python 2.7.2
>>> try:urllib2.urlopen('http://api.wordnik.com/v4/word.json/foo/examples')
... except urllib2.HTTPError as exc:
...   print(dir(exc))
...
['_HTTPError__super_init', '__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__getitem__', '__getslice__', '__hash__', '__init__', '__iter__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__setstate__', '__sizeof__', '__str__', '__subclasshook__', '__unicode__', '__weakref__', 'args', 'close', 'code', 'errno', 'filename', 'fileno', 'fp', 'getcode', 'geturl', 'hdrs', 'headers', 'info', 'message', 'msg', 'next', 'read', 'readline', 'readlines', 'strerror', 'url']

The same issue exists in Python 3.2.2.

Here's what I propose:
  - For Python 3.2 and 3.3, update HTTPError to supply a @property, aliasing .msg (will .msg always be a suitable .reason?).
  - For Python 2.7, document the deviance, such as by adding the following wording to the HTTPError docs: "Unlike URLError, HTTPError does not supply a reason attribute. The reason can be retrieved through the msg attribute."