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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 check_master(self):
        '''
        Log if the master is not running

        :rtype: bool
        :return: Whether or not the master is running
        '''
        if not os.path.exists(
                os.path.join(
                    self.opts['sock_dir'],
                    'publish_pull.ipc'
                    )
                ):
            return False
        return True