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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 rrc(self, r):
 """ Does a ROTATION to the RIGHT |>> """

        if not is_number(self.regs[r]):
            self.set(r, None)
            self.set_flag(None)
            return

        v_ = self.getv(self.regs[r]) & 0xFF
        self.regs[r] = str((v_ >> 1) | ((v_ & 1) << 7))