For something that trivial just include it in the body of the email, don't make people go out to a static foreign site to know what you are talking about. About the only good exception to this is a db-fiddle website where you can actually execute the code being posted. (and you should still put the main parts of the question in the email even then).
I'm not sure why I'm getting the error message. It is something straightforward, but I'm stumped.
If someone could point me in the right direction, I would appreciate it.
You invented some create function syntax the system has no clue what to do with. There are only two mutually exclusive options for RETURNS, "rettype" or the word "TABLE" then a table specification. You seem to somehow wish to combine them, dropping the word TABLE.