Combine lines of 2 files

zip(fh1, fh2)

Combine each line from first file with the corresponding line in second file.

with open('abc_colors.txt') as fh1, open('abc_text.txt') as fh2:

    for line1, line2 in zip(fh1, fh2):

        # line1 from abc_colors.txt, line2 from abc_text.txt
        print(line1 + line2)

Output:

Red
Welcome to pyHowTo [in Red].

Green
Welcome to pyHowTo [in Green].

Blue
Welcome to pyHowTo [in Blue].

See also

https://www.w3resource.com/python-exercises/file/python-io-exercise-14.php