Regular expresssion to extract the headers between two lines

I'm trying to extract a headers between the two dotted line

        ------------------------------------------------------------------------------------------
        PortNo    Descr                    Status         Speed     Mode        Pause     FlowCtrl
        ------------------------------------------------------------------------------------------
         1       A                           UP           200G      FULL         NO       YES

I wrote this regular expression to get the headers alone

header = re.search(r'--+\n(.*)\n--+', cli_output).group(1)

I tried to use the regex

--+\n(.*)

which picks the 2 and 4th line. To restrict picking up the 4th line, I modified the regex as

--+\n(.*)\n--+

Now it does not match anything. Where am I going wrong here? I tried in https://regex101.com/ as well but it does not match.

Your regex requires that the second line of hyphens starts at the beginning of its line, but that is not the case: there are spaces in front of those hypens.

So replace that second \n with \s+:

re.search(r'--+\n(.*)\s+--+', cli_output)

Note that you shouldn't chain .group(1) immediately to that search call. It is good practice to first check whether you have a match or not:

match = re.search(r'--+\n(.*)\s+--+', cli_output)
if not match:
    print("there was no match of a heading")
else:
    header = match.group(1)
    print(header)