Regex expression for validating IPv4
regex = " ( ( [ 0-9 ] ▁ [ 1-9 ] [ 0-9 ] ▁ 1[0-9 ] [ 0-9 ] ▁ " \ "2[0-4 ] [ 0-9 ] ▁ 25[0-5 ] ) \\ . ) { 3 } " " ( [0-9 ] ▁ [ 1-9 ] [ 0-9 ] ▁ 1[0-9 ] [ 0-9 ] ▁ " \ "2[0-4 ] [ 0-9 ] ▁ 25[0-5 ] ) " NEW_LINE