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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 _process_rules(self, rules):
 """Process rules into cidr and non-cidr lists. Args: rules (list):
 Allowed Security Group ports and protocols. Returns: (list, list):
 Security Group reference rules and custom CIDR rules. """

        cidr = []
        non_cidr = []

        for rule in rules:
            if '.' in rule['app']:
                self.log.debug('Custom CIDR rule: %s', rule)
                self._validate_cidr(rule)
                cidr.append(rule)
            else:
                self.log.debug('SG reference rule: %s', rule)
                non_cidr.append(rule)

        self.log.debug('Custom CIDR rules: %s', cidr)
        self.log.debug('SG reference rules: %s', non_cidr)
        return non_cidr, cidr