code: def _make_resolve_context(self):
          
          if self._is_missing_tags_strict():
              return context_get
          # Otherwise, ignore missing tags.
  
          def resolve_context(stack, name):
              try:
                  return context_get(stack, name)
              except KeyNotFoundError:
                  return u''
  
          return resolve_context
docs: Return the resolve_context function to pass to RenderEngine.__init__().