code: def update(self, friendly_name=values.unset, voice_fallback_method=values.unset,
                 voice_fallback_url=values.unset, voice_method=values.unset,
                 voice_status_callback_method=values.unset,
                 voice_status_callback_url=values.unset, voice_url=values.unset,
                 sip_registration=values.unset, domain_name=values.unset):
          
          return self._proxy.update(
              friendly_name=friendly_name,
              voice_fallback_method=voice_fallback_method,
              voice_fallback_url=voice_fallback_url,
              voice_method=voice_method,
              voice_status_callback_method=voice_status_callback_method,
              voice_status_callback_url=voice_status_callback_url,
              voice_url=voice_url,
              sip_registration=sip_registration,
              domain_name=domain_name,
          )
docs: Update the DomainInstance
  
          :param unicode friendly_name: A string to describe the resource
          :param unicode voice_fallback_method: The HTTP method used with voice_fallback_url
          :param unicode voice_fallback_url: The URL we should call when an error occurs in executing TwiML
          :param unicode voice_method: The HTTP method we should use with voice_url
          :param unicode voice_status_callback_method: The HTTP method we should use to call voice_status_callback_url
          :param unicode voice_status_callback_url: The URL that we should call to pass status updates
          :param unicode voice_url: The URL we should call when receiving a call
          :param bool sip_registration: Whether SIP registration is allowed
          :param unicode domain_name: The unique address on Twilio to route SIP traffic
  
          :returns: Updated DomainInstance
          :rtype: twilio.rest.api.v2010.account.sip.domain.DomainInstance