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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 execution_cls(self):
 """Get execution layer class """

        name = self.campaign.process.type
        for clazz in [ExecutionDriver, SrunExecutionDriver]:
            if name == clazz.name:
                return clazz
        raise NameError("Unknown execution layer: '%s'" % name)