This is a doctest, the content here is verbatim from the source file at pyogp.lib.base.tests.message_handler.txt.
>>> from pyogp.lib.base.message.message_handler import MessageHandler
>>> message_handler = MessageHandler()
>>> def callback(packet): print packet
>>> onStartPingCheck_received = message_handler.register("StartPingCheck")
>>> onStartPingCheck_received.subscribe(callback)
>>> from pyogp.lib.base.message.message import Message
>>> packet = Message('StartPingCheck')
>>> type(message_handler.handle(packet))
>>> Message