code: def url_regex_generator(*, relative: bool, require_tld: bool) -> Pattern[str]:
      
      return re.compile(
          r''.join(
              (
                  r'^',
                  r'(' if relative else r'',
                  r'(?:[a-z0-9\.\-\+]*)://',  # scheme is validated separately
                  r'(?:[^:@]+?:[^:@]*?@|)',  # basic auth
                  r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+',
                  r'(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}\.?)|',  # domain...
                  r'localhost|',  # localhost...
                  (
                      r'(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.?)|' if not require_tld else r''
                  ),  # allow dotless hostnames
                  r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}|',  # ...or ipv4
                  r'\[[A-F0-9]*:[A-F0-9:]+\])',  # ...or ipv6
                  r'(?::\d+)?',  # optional port
                  r')?' if relative else r'',  # host is optional, allow for relative URLs
                  r'(?:/?|[/?]\S+)$',
              )
          ),
          re.IGNORECASE,
      )
docs: Url regex generator taken from Marshmallow library,
      for details please follow library source code:
          https://github.com/marshmallow-code/marshmallow/blob/298870ef6c089fb4d91efae9ca4168453ffe00d2/marshmallow/validate.py#L37