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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 list_rocs_files(url=ROCS_URL):
 """Gets the contents of the given url. """

    soup = BeautifulSoup(get(url))
    if not url.endswith('/'):
        url += '/'
    files = []
    for elem in soup.findAll('a'):
        if elem['href'].startswith('?'):
            continue
        if elem.string.lower() == 'parent directory':
            continue
        files.append(url + elem['href'])
    return files