500 error handler.

    Templates: `500.html`
    Context: None

def handler500(request):
    """
    500 error handler.

    Templates: `500.html`
    Context: None
    """
    from django.template import Context, loader
    from django.http import HttpResponseServerError
    from overseer.context_processors import default
    import logging
    import sys
    try:
        context = default(request)
    except Exception, e:
        logging.error(e, exc_info=sys.exc_info(), extra={'request': request})
        context = {}
    
    context['request'] = request
    
    t = loader.get_template('500.html') # You need to create a 500.html template.
    return HttpResponseServerError(t.render(Context(context)))