code: def get(self, sid):
          
          return InstalledAddOnExtensionContext(
              self._version,
              installed_add_on_sid=self._solution['installed_add_on_sid'],
              sid=sid,
          )
docs: Constructs a InstalledAddOnExtensionContext
  
          :param sid: The unique Extension Sid
  
          :returns: twilio.rest.preview.marketplace.installed_add_on.installed_add_on_extension.InstalledAddOnExtensionContext
          :rtype: twilio.rest.preview.marketplace.installed_add_on.installed_add_on_extension.InstalledAddOnExtensionContext