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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 _run_pre_command(self, pre_cmd):
        '''
        Run a pre command to get external args for a command
        '''
        logger.debug('Executing pre-command: %s', pre_cmd)
        try:
            pre_proc = Popen(pre_cmd, stdout=PIPE, stderr=STDOUT, shell=True)
        except OSError as err:
            if err.errno == errno.ENOENT:
                logger.debug('Command %s not found', pre_cmd)
            return
        stdout, stderr = pre_proc.communicate()
        the_return_code = pre_proc.poll()
        logger.debug("Pre-command results:")
        logger.debug("STDOUT: %s", stdout)
        logger.debug("STDERR: %s", stderr)
        logger.debug("Return Code: %s", the_return_code)
        if the_return_code != 0:
            return []
        if six.PY3:
            stdout = stdout.decode('utf-8')
        return stdout.splitlines()