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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_template(self, source, **kwargs_context):
 r"""Render a template string using sandboxed environment. :param source: A string containing the page source. :param \*\*kwargs_context: The context associated with the page. :returns: The rendered template. """

        return self.jinja_env.from_string(source).render(kwargs_context)