my $ip_mask = parse_ip_mask('131.202.1.[3-4]');

foreach (qw(
   131.202.1.2
   131.202.1.3
   131.202.1.4
   132.202.1.4
)) {
   print(ip_check($_, $ip_mask)
      ? "$_ matches.$/"
      : "$_ doesn't match.$/"
   );
}

__END__
output
======
131.202.1.2 doesn't match.
131.202.1.3 matches.
131.202.1.4 matches.
132.202.1.4 doesn't match.