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Code: Alles auswählen

import os
import itertools
import shutil

def substitute_with(iterable, start, stop, content):
    iterable = iter(iterable)
    return itertools.chain(
        itertools.islice(iterable, start), content, itertools.islice(iterable, stop-start, None)
    )
 
 
def substitute_lines(filename, start, stop, content):
    tmp_filename = '{}.tmp'.format(filename)
    with open(filename, mode='r') as orig_file:
        with open(tmp_filename, mode='w') as tmp_file:
            try:
                tmp_file.writelines(
                    substitute_with(orig_file, start, stop, content)
                )
            except Exception:
                os.remove(tmp_filename)
                raise
    shutil.move(tmp_filename, filename)
 
if __name__ == '__main__':
    substitute_lines('lol.txt', 2,3, ['1\n'])