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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 PrependUOffsetTRelativeSlot(self, o, x, d):
 """ PrependUOffsetTRelativeSlot prepends an UOffsetT onto the object at vtable slot `o`. If value `x` equals default `d`, then the slot will be set to zero and no other data will be written. """


        if x != d:
            self.PrependUOffsetTRelative(x)
            self.Slot(o)