I've made a first release of GNOME Prepaid Manager a couple of days ago after switching to GTK+3, GSettings and PyGObject's GObject introspection but it still wasn't that useful since the very common Huawei chipsets (present in many UMTS USB sticks) weren't working due to some missing code in ModemManager.
Thanks to Dan's great description I just got around to add that which should make ppm useful to more people.
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