Pylons/pyramid — pull request #314 by jinty (2011-10-11 09:20:31+00:00)
Title: Convert unicode tokens to 'str'

This was resulting in unicode cookie values (and thus headers) on
Python 2 causing mod_wsgi to complain:
TypeError: expected string object for header value

PEP 3333 also says:
"Native" strings (which are always implemented using the type named
str) that are used for request/response headers and metadata

So mod_wsgi is right to complain about unicode headers and Pyramid is
wrong to send them.