code: def _render_content(self, content, **settings):
          
          if isinstance(content, dict):
              return self._render_content_dict(content, 0, [], **settings)
          elif isinstance(content, list):
              return self._render_content_list(content, 0, [], **settings)
          else:
              raise Exception("Received invalid data tree for rendering.")
docs: Render the tree widget.