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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 GetVOffsetTSlot(self, slot, d):
 """ GetVOffsetTSlot retrieves the VOffsetT that the given vtable location points to. If the vtable value is zero, the default value `d` will be returned. """


        N.enforce_number(slot, N.VOffsetTFlags)
        N.enforce_number(d, N.VOffsetTFlags)

        off = self.Offset(slot)
        if off == 0:
                return d
        return off