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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 refresh(self):
 """Refresh the dev_info data used by get_value. Only needed if you're not using subscriptions. """

        j = self.vera_request(id='sdata', output_format='json').json()
        devices = j.get('devices')
        for device_data in devices:
            if device_data.get('id') == self.device_id:
                self.update(device_data)