code: def _realGetLoader(n, default=_marker):
      
      for t in getAllThemes():
          fact = t.getDocFactory(n, None)
          if fact is not None:
              return fact
      if default is _marker:
          raise RuntimeError("No loader for %r anywhere" % (n,))
      return default
docs: Search all themes for a template named C{n}, returning a loader
      for it if found. If not found and a default is passed, the default
      will be returned. Otherwise C{RuntimeError} will be raised.
  
      This function is deprecated in favor of using a L{ThemedElement}
      for your view code, or calling
      ITemplateNameResolver(userStore).getDocFactory.