[Need Help] How is resourceManager accessed in jargon/alexa-skill-sdk

[AdarshNaidu]

According to this link.

We should be able to access the resourceManager using any of the following methods.

handlerInput.jrm
handlerInput.jargonResourceManager
handlerInput.attributesManager.getRequestAttributes().jrm
handlerInput.attributesManager.getRequestAttributes().jargonResourceManager

But I'm getting an error saying jargonResourceManager is not a function on calling handlerInput.jargonResourceManager(ri('key')).

What is the correct way of using these resource managers and is there any need to configure them before usage? If yes, how do we configure it?

Please point me to any code examples if possible