How to use regex (re)

[PK Khatri]

I have a following script which extracts xyz.tgz and outputs to a folder which contains several sub-folders and files. 

    source_dir = "c:\\TEST"
    dest_dir = "c:\\TEST"
    for src_name in glob.glob(os.path.join(source_dir, '*.tgz')):
        base = os.path.basename(src_name)
        dest_name = os.path.join(dest_dir, base[:-4])
        with tarfile.open(src_name, 'r') as infile:
            infile.extractall(dest_dir)

When above script is ran, the output is a single directory within that directory the structure looks like this:

folder_1
folder_2
folder_n
file_1
file_2
file_n

In these folder, there are sub-folders and files. Among those file there are some data i am interested in to search and output to a file.

For eg. Among the folders there is a file called **'localcli_network-ip-neighbor-list.txt**' which contains IP address(s) which I would like to output to a file.