code: def render(self, context):
          
          extra_context = self.context_expr.resolve(context)
          if not isinstance(extra_context, dict):
              raise TemplateSyntaxError("{% withdict %} expects the argument to be a dictionary.")
  
          with context.push(**extra_context):
              return self.nodelist.render(context)
docs: Render the tag, with extra context layer.