def logPageException(req: Request, message: str) -> None:
"""Logs an exception that occurred while handling a page request.
"""
logging.exception(
'%s:\n%s %s\n%s', message, req.method, req.getURL(),
getattr(req, 'args', '(before or during argument parsing)'))
def logoutURL(req: Request) -> str:
"""Returns a URL of the Logout page, so that it returns to the request's
URL after the user has logged out.
"""
return pageURL('Logout', URLArgs(url=req.getURL()))