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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_in_group(self):
 """Fetch list of devices in group."""

        try:
            devices = self.get_parameter('devices')
        except AttributeError:
            return []

        ctor = DeviceFactory
        return [ctor(int(x), lib=self.lib) for x in devices.split(',') if x]