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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 async_update(self, event, reason={}):
 """New event for sensor. Check if state or config is part of event. Signal that sensor has updated attributes. Inform what attributes got changed values. """

        reason['attr'] = []
        for data in ['state', 'config']:
            changed_attr = self.update_attr(event.get(data, {}))
            reason[data] = data in event
            reason['attr'] += changed_attr
        super().async_update(event, reason)