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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 devices(self):
 """List of devices to test """

        eax = self.attributes.get('devices')
        if eax is None:
            eax = self._all_devices
        if not isinstance(eax, list):
            eax = [eax]
        return [str(dev) for dev in eax]