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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 _get_ui_content(self, cli, width, height):
 """ Create a `UIContent` instance. """

        def get_content():
            return self.content.create_content(cli, width=width, height=height)

        key = (cli.render_counter, width, height)
        return self._ui_content_cache.get(key, get_content)