python doesn't append each line but skips some

Question

I have a complete_list_of_records which has a length of 550

this list would look something like this:

1. Apples

2. Pears

3. Bananas

The issue is that when i use:

 with open("recordedlines.txt", "a") as recorded_lines:
      for i in complete_list_of_records:
            recorded_lines.write(i)

the outcome of the file is 393 long and the structure someplaces looks like so

1. Apples

2. PearsBananas

3. Pineapples

I have tried with "w" instead of "a" append and manually inserted "\n" for each item in the list but this just creates blank spaces on every second row and still som rows have the same issue with dual lines in one.

Anyone who has encountered something similar?

Answer 1

From the comments seen so far, I think there are strings in the source list that contain newline characters in positions other than at the end. Also, it seems that some strings end with newline character(s) but not all.

I suggest replacing embedded newlines with some other character - e.g., underscore.

Therefore I suggest this:

with open("recordedlines.txt", "w") as recorded_lines:
      for line in complete_list_of_records:
            line = line.rstrip() # remove trailing whitespace
            line = line.replace('\n', '_') # replace any embedded newlines with underscore
            print(line, file=recorded_lines) # print function will add a newline

Answer 2

You could simply strip all whitespaces off in any case and then insert a newline per hand like so:

with open("recordedlines.txt", "a") as recorded_lines:
    for i in complete_list_of_records:
        recorded_lines.write(i.strip() + "\n")

Answer 3

you need to use

file.writelines(listOfRecords)

but the list values must have '\n'

f = open("demofile3.txt", "a")
li = ["See you soon!", "Over and out."]
li = [i+'\n' for i in li]
f.writelines(li)
f.close()

#open and read the file after the appending:
f = open("demofile3.txt", "r")
print(f.read())

output will be

See you soon!
Over and out.

you can also use for loop with write() having '\n' at each iteration