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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 turn_on(self):
 """Turn Air Purifier on"""

        if self.device_status != 'on':
            body = helpers.req_body(self.manager, 'devicestatus')
            body['uuid'] = self.uuid
            body['status'] = 'on'
            head = helpers.req_headers(self.manager)

            r, _ = helpers.call_api('/131airPurifier/v1/device/deviceStatus',
                                    'put', json=body, headers=head)

            if r is not None and helpers.check_response(r, 'airpur_status'):
                self.device_status = 'on'
                return True
            else:
                return False