PICO LCD GFX backlight setting by cheerlights

I am trying to get the cheerlights colour from https://io.adafruit.com/api/v2/cheerlights/feeds/hex/data to change the background colour
I’ve got the hex value ok
I’ve removed the leading # OK
I’ve converted hex to RGB OK

When I try to use board.set_backlight(rgb_conv) it fails with
TypeError: function takes 4 positional arguments but 2 were given

What do I use to get the converted hex into the board backlight?
Unless of course backlight can use hex, but docs doesn’t mention it.

Looks like I’ve fixed this.

Now to convert hex to a colour name.