IconTheme.lookupIcon

Looks up a named icon and returns a #GtkIconInfo containing information such as the filename of the icon. The icon can then be rendered into a pixbuf using gtk.icon_info.IconInfo.loadIcon. (gtk.icon_theme.IconTheme.loadIcon combines these two steps if all you need is the pixbuf.)

When rendering on displays with high pixel densities you should not use a size multiplied by the scaling factor returned by functions like gdk.window.Window.getScaleFactor. Instead, you should use gtk.icon_theme.IconTheme.lookupIconForScale, as the assets loaded for a given scaling factor may be different.