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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 PrependStructSlot(self, v, x, d):
 """ PrependStructSlot prepends a struct onto the object at vtable slot `o`. Structs are stored inline, so nothing additional is being added. In generated code, `d` is always 0. """


        N.enforce_number(d, N.UOffsetTFlags)
        if x != d:
            self.assertStructIsInline(x)
            self.Slot(v)