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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 _chosen_css(self):
 """Read the minified CSS file including STATIC_URL in the references to the sprite images."""

        css = render_to_string(self.css_template, {})
        for sprite in self.chosen_sprites:  # rewrite path to sprites in the css
            css = css.replace(sprite, settings.STATIC_URL + "img/" + sprite)
        return css