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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 master_pub(self):
        '''
        Return the master publish port
        '''
        return _get_master_uri(self.opts['master_ip'],
                               self.publish_port,
                               source_ip=self.opts.get('source_ip'),
                               source_port=self.opts.get('source_publish_port'))