with open("input-with-non-ascii.txt", "r", encoding="utf-8") as file: lines = file.readlines() cleaned_line = [i.encode("ascii", "ignore").decode() for i in lines] with open("output-without-non-ascii.txt", "w", encoding="utf-8") as file: file.writelines(cleaned_line) # Output: "This is a text with non-ASCII: cafe, resume, jalapeno."