(evt, callback)
Add a listener to an Event object. This may be called multiple
        times for the same event. Every time the event happens, the
        callback method will be called. The callback has one argument
        (a string, the contents of the event, minus the '650' and the
        name of the event)

        FIXME: should have an interface for the callback.
Add a listener to an Event object. This may be called multiple
        times for the same event. Every time the event happens, the
        callback method will be called. The callback has one argument
        (a string, the contents of the event, minus the '650' and the
        name of the event)
Add a listener to an Event object . This may be called multiple times for the same event . Every time the event happens the callback method will be called . The callback has one argument ( a string the contents of the event minus the 650 and the name of the event )
def add_event_listener(evt, callback):
        """
        Add a listener to an Event object. This may be called multiple
        times for the same event. Every time the event happens, the
        callback method will be called. The callback has one argument
        (a string, the contents of the event, minus the '650' and the
        name of the event)

        FIXME: should have an interface for the callback.
        """
def add_event_listener ( evt , callback ) :