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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_cached_style_urls(self, asset_url_path):
 """ Gets the URLs of the cached styles. """

        try:
            cached_styles = os.listdir(self.cache_path)
        except IOError as ex:
            if ex.errno != errno.ENOENT and ex.errno != errno.ESRCH:
                raise
            return []
        except OSError:
            return []
        return [posixpath.join(asset_url_path, style)
                for style in cached_styles
                if style.endswith('.css')]