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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 get_details(self):
 """Build details dictionary"""

        body = helpers.req_body(self.manager, 'devicedetail')
        head = helpers.req_headers(self.manager)

        r, _ = helpers.call_api('/131airpurifier/v1/device/deviceDetail',
                                method='post', headers=head, json=body)

        if r is not None and helpers.check_response(r, 'airpur_detail'):
            self.device_status = r.get('deviceStatus', 'unknown')
            self.connection_status = r.get('connectionStatus', 'unknown')
            self.details['active_time'] = r.get('activeTime', 0)
            self.details['filter_life'] = r.get('filterLife', {})
            self.details['screeen_status'] = r.get('screenStatus', 'unknown')
            self.details['mode'] = r.get('mode', 'unknown')
            self.details['level'] = r.get('level', None)