Testing simple project script

I am new to project scripts and was just trying to test the simple example in the manual but I get a error when I try to run it.

Traceback (most recent call last):
File “event:actionPerformed”, line 1, in
AttributeError: ‘com.inductiveautomation.ignition.common.script.Scr’ object has no attribute ‘functions’

#display popup message
def popMessage(message):
    system.gui.messageBox(message)

you have to add the package name before your project script name.

project.js.functions.popMessage(‘Hello World’)