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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 mpirun(self):
 """Additional options passed as a list to the ``mpirun`` command"""

        cmd = self.attributes['mpirun']
        if cmd and cmd[0] != 'mpirun':
            cmd = ['mpirun']
        return [str(e) for e in cmd]