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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 dns_name(self):
 """Get the DNS name for this machine. This is a best guess based on the addresses available in current data. May return None if no suitable address is found. """

        for scope in ['public', 'local-cloud']:
            addresses = self.safe_data['addresses'] or []
            addresses = [address for address in addresses
                         if address['scope'] == scope]
            if addresses:
                return addresses[0]['value']
        return None