How to customize the column header of the delivered Spreadsheet loader of External data?

Summary:

We have a requirement, if possible, to change the Column headers of the External data columns spreadsheet loader.

The spreadsheet loader that I am referring to is the one that is downloaded when you click 'Prepare Import Spreadsheet' in the External Data page as shown below.

Thank you in advance for your answers.

Best Regards,

Fatima

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