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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 rule_low_registers(self, arg):
 """Low registers are R0 - R7"""

        r_num = self.check_register(arg)
        if r_num > 7:
            raise iarm.exceptions.RuleError(
                "Register {} is not a low register".format(arg))