How Can I Type Rainbow Text In My Garry's Mod Server?

So I have seen some GMod servers that when you type something like <hsv>Text Goes Here</hsv> it will make the text in-between flash rainbow. I don’t know if that requires code to put on my server, but if it does, could anyone please help me? Thanks.

It’s a paid chatbox from ScriptFodder.

The HSV stands for Hue, Saturation, and Value

Garry’s Mod has made available functions such as

HSVToColor which allow you to convert CurTime() and other sorts of time measurements as multipliers into colors.

I don’t believe the regular chatbox has a constantly running hook (Think/Tick) so it may not be possible off the bat unless you modify it to have one.

I made a GitHub repository ages ago featuring functions you can use for drawing all sorts of rainbow things, including rainbow text in the default chatbox.