500 error

unbound method get() must be called with Custom404View instance as first argument (got WSGIRequest instance instead)

Traceback (most recent call last):

File "/var/www/django/gbn.moscow/venv/local/lib/python2.7/site-packages/django/core/handlers/exception.py", line 116, in get_exception_response
response = callback(request, **param_dict)

TypeError: unbound method get() must be called with Custom404View instance as first argument (got WSGIRequest instance instead)