Looking at the Totem code, it looks like a set of GktButtons inside a GtkToolbar, with a CSS style applied and using symbolic icons (which are also installed by the theme in Ubuntu) instead of the stock ones.

Here's an example in Python

# Assuming builder is an initialized Gtk.Builder object and toolbar exists

# in the .ui definition file and is populated with Gtk.ToolButtons



context = builder.get_object('toolbar').get_style_context()

context.add_class(Gtk.STYLE_CLASS_INLINE_TOOLBAR)

More info on GTK+ 3 CSS styles:

• The GNOME journal: styling GTK with CSS


• GtkCssProvider documentation