code: def get_installed_extensions(self, contribution_ids=None, include_disabled_apps=None, asset_types=None):
          
          query_parameters = {}
          if contribution_ids is not None:
              contribution_ids = ";".join(contribution_ids)
              query_parameters['contributionIds'] = self._serialize.query('contribution_ids', contribution_ids, 'str')
          if include_disabled_apps is not None:
              query_parameters['includeDisabledApps'] = self._serialize.query('include_disabled_apps', include_disabled_apps, 'bool')
          if asset_types is not None:
              asset_types = ":".join(asset_types)
              query_parameters['assetTypes'] = self._serialize.query('asset_types', asset_types, 'str')
          response = self._send(http_method='GET',
                                location_id='2648442b-fd63-4b9a-902f-0c913510f139',
                                version='5.0-preview.1',
                                query_parameters=query_parameters)
          return self._deserialize('[InstalledExtension]', self._unwrap_collection(response))
docs: GetInstalledExtensions.
          [Preview API]
          :param [str] contribution_ids:
          :param bool include_disabled_apps:
          :param [str] asset_types:
          :rtype: [InstalledExtension]