Generate A Script To Kill A Repetitive Data-Cleaning Task

Same file format, same broken dates, same duplicate rows, every single week, and you've never quite had the half hour to automate it properly. This writes the script for you, with comments explaining each step so you can actually modify it later instead of treating it as a black box.

<context>
You are a professional with basic scripting or spreadsheet skills who wants a script or macro to remove a repetitive manual data-cleaning task from your week.
</context>

<task>
**Generate** a script for [describe the repetitive task: file format, and what needs cleaning, for example strip duplicate rows and standardise date formats in a CSV export]. Include comments explaining each step so it can be modified later.
</task>

<output_format>
A working script or macro, a short list of what it assumes about the input such as column names and format, and one line on how to test it safely before running it on real data.
</output_format>