How to remove duplicates from the result in parsing?

Question

Python

def bf_parse(base_url, headers):
    session = requests.session()
    request = session.get(base_url, headers=headers)
    if request.status_code == 200:
        soup = bs(request.content, 'html.parser')
        links = [link.get('href') for link in soup.find_all('a', title='Просмотр профиля')]
        f = open("user_baza.txt", "a")
        f.write('\n'.join(links))
        f.close()
        print('\n'.join(links))
    else:
        print("Ссылки на пользователей на этой страницы кончились, замените парс-ссылку")


bf_parse(base_url, headers)

What needs to be built into the code so that all duplicates (in the form of links) are removed?