(GTK+ 3.4.2, Python 3.2.3, Linux Mint Debian Edition, Cinnamon Desktop)
For a GtkImageMenuItem I defined a GTK stockicon. But its size is too big for my taste. How can I change the size? set_pixel_size() does not have any visible effect. I found
information about GtkIconSize, but I don't know how to apply it. Thank you!

Code:
self.menuitem01_01 = Gtk.ImageMenuItem(label="Neu")
self.menuitem01_01icon = Gtk.Image(stock="gtk-new")
self.menuitem01_01icon.set_pixel_size(100)
self.menuitem01_01.set_image(self.menuitem01_01icon)
self.menu01.add(self.menuitem01_01)