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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 extract(self, item, list_article_candidate):
 """Compares the extracted descriptions. :param item: The corresponding NewscrawlerItem :param list_article_candidate: A list, the list of ArticleCandidate-Objects which have been extracted :return: A string, the most likely description """

        list_description = []

        """ The descriptions of the article candidates and the respective extractors are saved
        in a tuple in list_description.
        """
        for article_candidate in list_article_candidate:
            if article_candidate.description != None:
                list_description.append((article_candidate.description, article_candidate.extractor))

        # If there is no value in the list, return None.
        if len(list_description) == 0:
            return None

        # If there are more options than one, return the result from newspaper.
        list_newspaper = [x for x in list_description if x[1] == "newspaper"]
        if len(list_newspaper) == 0:

            # If there is no description extracted by newspaper, return the first result of list_description.
            return list_description[0][0]
        else:
            return list_newspaper[0][0]