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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def group_num(self):
 """Current group number. :getter: Returns current group number :setter: Sets current group number :type: int """

        xkb_state = XkbStateRec()
        XkbGetState(self._display, XkbUseCoreKbd, byref(xkb_state))
        return xkb_state.group