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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 do_render(parser, token):
 """ Renders a rich-text field using defined markup. Example:: {% render some_var %} """

    bits = token.split_contents()

    if len(bits) != 2:
        raise template.TemplateSyntaxError()

    return RenderNode(bits[1])