def add_event()

in operators.py [0:0]


    def add_event(self, event_type, message, long_message):
        props = bpy.context.scene.meshgen_props
        event = props.history.add()
        event.type = event_type
        if message:
            event.content = message
        if long_message:
            lines = str(long_message).split("\n")
            for line in lines:
                self.log_text.write(line + "\n")