Python Paste: evalerror middleware

Notes: this is part of Python Paste; the code is in the repository in paste.evalexception. The Paste Deploy configuration file I use is:

[server:main]
use = egg:PasteScript#wsgiutils
port = 9999

[filter-app:main]
use = egg:Paste#evalerror
next = filter

[app:filter]
use = egg:PasteScript#test