Adding our own custom coded Property Tokens in File Name and Location Template

Is there a way to add our own custom coded Property Tokens in the File Name and Location Template?

For example, if I wanted to add a custom token that doesn't exist already like a username/artist token to attach the artist name who rendered the image sequence, is there a place I can do that? Is there a script file that contains these Property Tokens somewhere in the Support Files or App Data or something like that and can be modified?

I'm not asking how to write that code, just if and where I can write that code to add our own custom Property Tokens to the File Name and Location Templates module:

Thanks.