I used UPS many years ago for regular shipping to the US, this was well before electronic transmission of customs information. At that time the customs documents were completely separate from the actual shipping label (1 or 2 pages enclosed in a pouch on the outside of the package).
Currently I'm using APC or PostNL via Stallion, the APC labels have the customs info integrated, the PostNL labels do not (just address and bar code). For both the customs declaration has to be inputted to be able to print a label.

"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915
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