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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 eq(self, r1, r2):
 """ True if values of r1 and r2 registers are equal """

        if not is_register(r1) or not is_register(r2):
            return False

        if self.regs[r1] is None or self.regs[r2] is None:  # HINT: This's been never USED??
            return False

        return self.regs[r1] == self.regs[r2]