Writing a list to a file with Python, with newlines

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Use a loop:

with open('your_file.txt', 'w') as f:
    for line in lines:
        f.write(f"{line}\n")

For Python <3.6:

with open('your_file.txt', 'w') as f:
    for line in lines:
        f.write("%s\n" % line)

For Python 2, one may also use:

with open('your_file.txt', 'w') as f:
    for line in lines:
        print >> f, line

If you’re keen on a single function call, at least remove the square brackets [], so that the strings to be printed get made one at a time (a genexp rather than a listcomp) — no reason to take up all the memory required to materialize the whole list of strings.

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