Extract the link

import re

pattern = r'((www)\.([A-Za-z0-9]+(\-[A-Za-z0-9]+)*(\.[a-z]+)+))'
some_sentance = input()
valid_urls = []

while some_sentance:
    matches = re.finditer(pattern, some_sentance)
    for match in matches:
        valid_urls.append(match.group(1))
    some_sentance = input()
for valid_url in valid_urls:
    print(valid_url)