Regular filtering of Intranet addresses and segments

1. Problem description

I want to filter out ABC Intranet address and CIDR Format Intranet IP paragraph
Mainly the following paragraphs
1.A Class address :10.0.0.0～10.255.255.255
2.B Class address :172.16.0.0 ～172.31.255.255
3.C Class address :192.168.0.0～192.168.255.255

2. solve the problem

Regular expressions ：

^(10\.\d{
    1,3}\.\d{
    1,3}\.((0\/([89]|1[0-9]|2\d|3[012]))|(\d{
    1,3})))|(172\.(1[6789]|2\\d|3[01])\.\d{
    1,3}\.\d{
    1,3}(\/(1[6789]|2\d|3[012]))?)|(192\.168\.\d{
    1,3}\.\d{
    1,3}(\/(1[6789]|2\d|3[012]))?)$

Python give an example

# ABC Intranet address detection 
def check_intranet_ip_segment(ip):
    '''  matching  1.A Class address :10.0.0.0~10.255.255.255 2.B Class address :172.16.0.0~172.31.255.255 3.C Class address :192.168.0.0~192.168.255.255  Match successfully returns True, conversely False '''
    result = re.match(r'^(10\.\d{1,3}\.\d{1,3}\.((0\/([89]|1[0-9]|2\d|3[012]))|(\d{1,3})))|(172\.(1[6789]|2\\d|3[01])\.\d{1,3}\.\d{1,3}(\/(1[6789]|2\d|3[012]))?)|(192\.168\.\d{1,3}\.\d{1,3}(\/(1[6789]|2\d|3[012]))?)$', ip)
    if result:
        return True
    else:
        return False