Using regex to remove a string

Question

Ok, so I am currently trying to remove a string from the result of a readable text file there just IP addresses and hostnames. I'm attempting to get rid of the hostnames and just have the IP addresses so that I can then scan the result which should be the left over IP addresses.

with open('test.txt','r') as f:
  for line in f:
         subst = ""
         test_str = line
         result = re.sub("[a-zA-Z]", subst, test_str, 0)
         if result:
                 print(result)

With this, I can remove the letters from the host names in the file which gives me these.

89008..9..

29014..9..

121.25.30.237

143.55.50.238

162.34.50.149

89008..9..

19002..9..

The left over numbers above and below the IP's are whats remaining of the host names. Is there any way I can get rid of the remaining number only leaving the IP's? aka just 121.25.30.237, 143.55.50.238, and 162.34.50.149 I've been using regex101 to test random things but I can't seem to find what I need.

score 2 · Accepted Answer · edited Aug 21 '17 at 14:39

2

You could use this Regex to capture the remaining IP addresses?

^((\d{1,3}\.){3}\d{1,3})$

^ start of string
\d digit
{1,3} 1-3 times
\. character "."
$ End of String

edited Aug 21 '17 at 14:39

clabe45

2,354
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answered Aug 17 '17 at 15:16

user8478480

427
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Using regex to remove a string

1 Answers1