Node-red 1.3 function Modules problem

How do modules imported from function nodes be invoked in functions? thank you

It depends on the library that you have required but for the above example :

[{"id":"0bd4a2216f8d1ed7","type":"inject","z":"4895ea10b4ee9ead","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":370,"y":1000,"wires":[["a6b4049859c21f21"]]},{"id":"a6b4049859c21f21","type":"function","z":"4895ea10b4ee9ead","name":"","func":"msg.payload = cowsay2.say('hi')\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[{"var":"cowsay2","module":"cowsay2"}],"x":550,"y":1000,"wires":[["2cfb705c6e0cbcb2"]]},{"id":"2cfb705c6e0cbcb2","type":"debug","z":"4895ea10b4ee9ead","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":730,"y":1000,"wires":[]}]

Thank you very much UnborN
The imported module is ready for use