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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 sitemap_check(url):
 """ Sitemap-Crawler are supported by every site which have a Sitemap set in the robots.txt. :param str url: the url to work on :return bool: Determines if Sitemap is set in the site's robots.txt """

        response = urllib2.urlopen(UrlExtractor.get_sitemap_url(url, True))

        # Check if "Sitemap" is set
        return "Sitemap:" in response.read().decode('utf-8')