m/([01]?\d\d?|2[0-4]\d|25[0-5])
   \.
  ([01]?\d\d?|2[0-4]\d|25[0-5])
  \.
  ([01]?\d\d?|2[0-4]\d|25[0-5])
  \.
  ([01]?\d\d?|2[0-4]\d|25[0-5])(.*)/x

##</code><code>##

'23.165.2.40'       '23.165.2.40'
'(23.165.2.40)'     '23.165.2.40'
'[23.165.2.40]'     '23.165.2.4'
'{23.165.2.40}'     '23.165.2.4'