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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_url_file_name(url):
 """ Determines the url's file name. :param str url: the url to extract the file name from :return str: the filename (without the file extension) on the server """

        url_root_ext = os.path.splitext(url)

        if len(url_root_ext[1]) <= MAX_FILE_EXTENSION_LENGTH:
            return os.path.split(url_root_ext[0])[1]
        else:
            return os.path.split(url)[1]