Mod_python error: "PythonHandler mod_python.publisher"

Traceback (most recent call last):

  File "/usr/lib64/python2.4/site-packages/mod_python/apache.py", line 299, in HandlerDispatch
    result = object(req)

  File "/usr/lib64/python2.4/site-packages/mod_python/publisher.py", line 213, in handler
    published = publish_object(req, object)

  File "/usr/lib64/python2.4/site-packages/mod_python/publisher.py", line 412, in publish_object
    return publish_object(req,util.apply_fs_data(object, req.form, req=req))

  File "/usr/lib64/python2.4/site-packages/mod_python/util.py", line 439, in apply_fs_data
    return object(**args)

  File "/var/www/vhosts/visitflanders/htdocs/do/ecco.py", line 261, in cview
    (listcode, catcode, itemcode, ctags) = EccoViewAction.split_codes(codes)

  File "/var/www/vhosts/visitflanders/htdocs/do/eccocms/EccoViewAction.py", line 303, in split_codes
    assert (len(codes)==1 or len(codes)==2), "cview only accepts 1 or 2 codes!"

AssertionError: cview only accepts 1 or 2 codes!