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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 add_rules(self, rules: _RuleList) -> None: """Appends new rules to the router. :arg rules: a list of Rule instances (or tuples of arguments, which are passed to Rule constructor). """

        for rule in rules:
            if isinstance(rule, (tuple, list)):
                assert len(rule) in (2, 3, 4)
                if isinstance(rule[0], basestring_type):
                    rule = Rule(PathMatches(rule[0]), *rule[1:])
                else:
                    rule = Rule(*rule)

            self.rules.append(self.process_rule(rule))