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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_not_from_subdomain(self, response, site_dict):
 """ Ensures the response's url isn't from a subdomain. :param obj response: The scrapy response :param dict site_dict: The site object from the JSON-File :return bool: Determines if the response's url is from a subdomain """


        root_url = re.sub(re_url_root, '', site_dict["url"])
        return UrlExtractor.get_allowed_domain(response.url) == root_url