code: def get_index(self, name):
          
          catalog = self.get_catalog()
          index = catalog._catalog.getIndex(name)
          logger.debug("get_index={} of catalog '{}' --> {}".format(
              name, catalog.__name__, index))
          return index
docs: get an index by name
  
          TODO: Combine indexes of relevant catalogs depending on the portal_type
          which is searched for.