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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, template, context_stack, delimiters=None):
 """ Render a unicode template string, and return as unicode. Arguments: template: a template string of type unicode (but not a proper subclass of unicode). context_stack: a ContextStack instance. """

        parsed_template = parse(template, delimiters)

        return parsed_template.render(self, context_stack)