Find specific subdir, open files and find specific lines that are missing from a file

[Gribouillis]

You could try something along the line of

import re

with open (hdir_f1) as cells_file:
    inum = set(int(match.group(1)) for match in
        (re.search(r"CELL\-(\d+)", line) for line in cells_file) if match)
    for i in range(1, 13):
        print('line CELL-{} - {}'.format(
            i, 'infile' if i in inum else 'missing'))