def update(self, friendly_name=values.unset, device_sid=values.unset):
data = values.of({'<STR_LIT>': friendly_name, '<STR_LIT>': device_sid, })<EOL>payload = self._version.update(<EOL>'<STR_LIT:POST>',<EOL>self._uri,<EOL>data=data,<EOL>)<EOL>return KeyInstance(<EOL>self._version,<EOL>payload,<EOL>fleet_sid=self._solution['<STR_LIT>'],<EOL>sid=self._solution['<STR_LIT>'],<EOL>)<EOL>
Update the KeyInstance

:param unicode friendly_name: The human readable description for this Key.
:param unicode device_sid: The unique identifier of a Key to be authenticated.

:returns: Updated KeyInstance
:rtype: twilio.rest.preview.deployed_devices.fleet.key.KeyInstance