github.com/gotd/td/tg.WallPaperClassArray.Retain (method)

one use

	github.com/gotd/td/tg (current package)
		tl_wall_paper_slices_gen.go#L57: func (s WallPaperClassArray) Retain(keep func(x WallPaperClass) bool) WallPaperClassArray {