Insert one multiline txt file into another line by line

July 18, 2022

I have two multiline txt files.
File1 :

- one 
- two 
- three

File2 :

- uno
- dos
- tres

I would like to create a merged file that looks like this :

- one
 - uno
- two
 - dos
- three
 - tres

So far I have only found one solution that can do this:

import itertools
with open('file1.txt', 'r') as f1, open('file2.txt', 'r') as f2:

# Merge data:
w1 = [line.strip() for line in f1]
w2 = [line.strip() for line in f2]
iters = [iter(w1), iter(w2)]
result = list(it.next() for it in itertools.cycle(iters))

# Save data:
result_file = open('result.txt', 'w')
for line in result:
    result_file.write("{}\n".format(line))
result_file.close()

but I keep on getting the error message.
AttributeError: ‘list_iterator’ object has no attribute ‘next’

Can someone tell me what I did wrong, is there a better way to achieve this? Thanks in advance!

>Solution :

Files are iterators, so you can zip them:

with open('file1.txt') as f1, open('file2.txt') as f2, open('result.txt', 'w') as out:
    for line1, line2 in zip(f1, f2):
        out.write(line1)
        out.write('  ')
        out.write(line2)