import requests

def check_last_file(text):
    if text[:2] = 'We':
        return True
    else:
        return False

def get_url_from_file(file):
    with open(file) as f:
        name = f.readline().strip('\n')
    return name

def go_through_chain(url):
    print('I\'m going go to url: %s' % url)
    query = request.get(url)
    content = query.text
    if not check_last_file(content):
        go_through_chain(content)
    else:
        print('URL %s - is FINAL!!!' % content)


if __name__ == '__main__':
    address = 'https://stepic.org/media/attachments/course67/3.6.3/'

    first_step_file = str(input('Enter first file name: '))
    url = address + get_url_from_file(first_step_file)
    go_through_chain(url)