def update(self, date_expiry=values.unset, ttl=values.unset, mode=values.unset,<EOL>status=values.unset, participants=values.unset):
data = values.of({<EOL>'<STR_LIT>': serialize.iso8601_datetime(date_expiry),<EOL>'<STR_LIT>': ttl,<EOL>'<STR_LIT>': mode,<EOL>'<STR_LIT>': status,<EOL>'<STR_LIT>': serialize.map(participants, lambda e: serialize.object(e)),<EOL>})<EOL>payload = self._version.update(<EOL>'<STR_LIT:POST>',<EOL>self._uri,<EOL>data=data,<EOL>)<EOL>return SessionInstance(<EOL>self._version,<EOL>payload,<EOL>service_sid=self._solution['<STR_LIT>'],<EOL>sid=self._solution['<STR_LIT>'],<EOL>)<EOL>
Update the SessionInstance

:param datetime date_expiry: The ISO 8601 date when the Session should expire
:param unicode ttl: When the session will expire
:param SessionInstance.Mode mode: The Mode of the Session
:param SessionInstance.Status status: The new status of the resource
:param dict participants: The Participant objects to include in the session

:returns: Updated SessionInstance
:rtype: twilio.rest.proxy.v1.service.session.SessionInstance