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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 srun(self):
 """Get path to srun executable :rtype: string """

        commands = self.campaign.process.get('commands', {})
        srun = find_executable(commands.get('srun', 'srun'))
        if six.PY2:
            srun = srun.encode('utf-8')
        return srun