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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 is_external_url(self, url, site_url):
 """ Check if the URL is an external URL. """

        url_splitted = urlsplit(url)
        if not url_splitted.netloc:
            return False
        return url_splitted.netloc != urlsplit(site_url).netloc