Feature or enhancement

Add support for PGM, PPM, and PNG formats toturtle.bgpic() andturtle.register_shape().

Pitch

Currently,turtle only supports GIF format for an image file,
where as the backendtkinter.PhotoImage supports PGM, PPM, and PNG formats in addition to GIF format.
Ifturtle supports PNG format, you can animate true color images.
(It helps teaching Python withturtle, because you can search PNG images more easily than GIF ones on Internet.)
Also it would be consistent ifturtle supports all formats thattkinter supports.

Linked PRs

• gh-95371: Add support for other image formats(e.g. PNG) to the turtle… #95378