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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_hostname_cn_ip(self, addresses):
 """Add an address to the SAN list for the hostname request :param addr: [] List of address to be added """

        for addr in addresses:
            if addr not in self.hostname_entry['addresses']:
                self.hostname_entry['addresses'].append(addr)