Help with reversing characters in a string (6)

1 Name: Cassie : 20/08/26(Wed)15:28 ID:9yo2ZPw8 [Del]

Hi all, I am not sure if this is the right place to post this but I have having trouble reversing a single line of text within a file.

My Input: File.txt

cat File.txt
ONE
TWO
THREE

My desired output: Updated_File.txt
cat Updated_File.txt
ONE
OWT
THREE

So basically I want to 'rev' but for only specific lines within a file. Is there any way to direct rev to only specific lines within a file? Or is there a better way to achieve this?

Thanks!

2 Name: Cassie : 20/08/26(Wed)16:15 ID:9yo2ZPw8 [Del]

Got it! please disregard the question

3 Post deleted by user.

4 Name: Davis : 20/08/30(Sun)20:29 ID:7xzDrQHw [Del]

Glad you got it! How'd you end up solving it?

5 Name: Wesley!yumibfYFn. : 20/08/31(Mon)09:46 ID:8QsJoisv [Del]

I'd also be interested in the solution. I can probably write a Perl one-liner for this but it'd take most of my morning.

6 Name: Davis : 20/08/31(Mon)17:36 ID:7xzDrQHw [Del]

I'd probably use Python or Lua, just because I value my sanity :)

Is it based on line number, or matching a pattern?

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