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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(self, context):
 """ Render the tag, with extra context layer. """

        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)