Someone

import gtk
import gtk.glade

import os
import os.path

factory = gtk.IconFactory()

for pixmap in os.listdir('pixmaps'):
    if pixmap.endswith('.png'):
        iconsrc = gtk.IconSource()
        iconsrc.set_filename(os.path.join(os.getcwd(), 'pixmaps', pixmap))
        iconsrc.set_direction_wildcarded(True)
        iconsrc.set_state_wildcarded(True)
        iconsrc.set_size_wildcarded(True)
        iconset = gtk.IconSet()
        iconset.add_source(iconsrc)
        factory.add('shy-'+pixmap[:-4], iconset)
factory.add_default()

print "**", gtk.icon_factory_lookup_default('shy-add-mesh')

ui = gtk.glade.XML('test.glade', "main")

gtk.main()