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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, **kwargs):
 """ Render template. :param context: A dict or dict-like object to instantiate given template file :param kwargs: Keyword arguments passed to the template engine to render templates with specific features enabled. :return: Rendered string """

        # Not pass both searchList and namespaces.
        kwargs["namespaces"] = [context, ] + kwargs.get("namespaces", []) \
                                           + kwargs.get("searchList", [])
        kwargs["searchList"] = None

        # TODO:
        # if at_paths is not None:
        #    paths = at_paths + self._engine_valid_opts.get(..., [])
        #    ...
        kwargs = self.filter_options(kwargs, self.engine_valid_options())
        self.engine_options.update(kwargs)

        return render_impl(**self.engine_options)