commutesByPerson person = liftIO $ do
  work <- getCommutes (Destination person Work)
  appt <- getCommutes (Destination person Appt)
  return $ work ++ appt
commutesByPerson person = liftIO $ do
  work <- getCommutes (Destination person Work)
  appt <- getCommutes (Destination person Appt)
  return $ work ++ appt
commutesByPerson person = liftIO $ do
  work <- getCommutes (Destination person Work)
  appt <- getCommutes (Destination person Appt)
  return $ work ++ appt