While working on the API of LinkedIn we had to a query in this format:

http://api.linkedin.com/v1/people/~/network?type=STAT&type=PICT&count=50&start=50

As usual, you get a 401 (forbidden) response. That was tough bug. Thank to LinkedIn forum I found out that in the python-oauth library you cannot have a query parameter with multiple values. Adam from the LinkedIn forum pointed out that have multiple values is valid according to the OAuth 1.0 spec and there is support in the python-oauth2 library.

If you want this functionality in python-oauth (OAuth 1.0) take a look at the following gist.