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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _render_content(self, content, **settings):
 """ Render the tree widget. """

        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.")