pandas - Python - Horizontal Customer Data to Vertical

Question

I am trying to take customer data in the below "horizontal" format and shift into a vertical format.

Currently, the data is in the below format for reference.

I am looking to transpose the data into the below format where each row represents a particular transaction with columns for the customer, date, and product.

Would the best method be to create separate data frames for each customer/product and then concat all of the dataframes?

Answer 1

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