import re
o = r'(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9][0-9]?)'
regex = fr'\b{o}(?:\.{o}){{3}}\b'
# OR regex = fr'(?<!\d)(?<!\d\.){o}(?:\.{o}){{3}}(?!\.?\d)'
url_string = "http://110.234.52.124/paypal.ca/index.html"
print( bool(re.search(regex, url_string, re.X)) )