Is there a way to store additional data related to a contract through a spreadsheet upload?

Summary:

I'm looking to import data related to authorized signers who need to approve contracts. It looks like a spreadsheet can be uploaded but the data fields need to be mapped to predefined fields related to creating / updating a contract. Does anyone know if it is possible to upload data that would fall outside of the template?

Here is the documentation that I was reading - https://docs.oracle.com/en/cloud/saas/sales/20b/oacts/data-import-and-export.html#OACTS336842.

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