docs: def _webTranslator(store, fallback):
      """
      Discover a web translator based on an Axiom store and a specified default.
      Prefer the specified default.
  
      This is an implementation detail of various initializers in this module
      which require an L{IWebTranslator} provider.  Some of those initializers
      did not previously require a webTranslator, so this function will issue a
      L{UserWarning} if no L{IWebTranslator} powerup exists for the given store
      and no fallback is provided.
  
      @param store: an L{axiom.store.Store}
      @param fallback: a provider of L{IWebTranslator}, or None
  
      @return: 'fallback', if it is provided, or the L{IWebTranslator} powerup on
      'store'.
      """
      if fallback is None:
          fallback = IWebTranslator(store, None)
          if fallback is None:
              warnings.warn(
                  "No IWebTranslator plugin when creating Scrolltable - broken "
                  "configuration, now deprecated!  Try passing webTranslator "
                  "keyword argument.", category=DeprecationWarning,
                  stacklevel=4)
      return fallback