This program consists of two parts. One is a server side (GAE) program and other one is a command line program. First you access the server side program on GAE, the program provides a client id (number) as the last segment of URL. Next you post messages using the client id from the command line program as followings:

gophernotify -m "Hello, Gophers" -c 1

This example uses 1 as client id and posts "Hello, Gophers" to the GAE server. And you can see the message on a browser without reload.