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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 merge_list(self, new_list):
 """Add new CM servers to the list :param new_list: a list of ``(ip, port)`` tuples :type new_list: :class:`list` """

        total = len(self.list)

        for ip, port in new_list:
            if (ip, port) not in self.list:
                self.mark_good((ip, port))

        if len(self.list) > total:
            self._LOG.debug("Added %d new CM addresses." % (len(self.list) - total))