Read Multiples Text Files get specific lines based criteria

[menator01]

This works for me

# /usr/bin/env python3

import os

for root, dirs, files in os.walk('./', topdown=True):

    for name in files:
        if 'txt' in name:
            with open(name, 'r') as lines:
                for line in lines:
                    for word in line.split():
                        if '|D100|' in word:
                            print(line) 

Output:
this is some text with |D100|

text with |D100|

still more |D100|

one more text with |D100|

Directory structure

Output:
├── another.txt
├── my.txt
└── walk.py

Contents of my.txt
this is some text with |D100|
this text does not have it
more text
text with |D100|

Contents of another.txt
This is another file text
More here
still more |D100|
one more text with |D100|