Proof of artistía? Wait, "Artist proof" as a term. In Portuguese, "Artist proof" is commonly translated as "Prova de artista" or "Artist Proof"? The instruction: Do not translate product names, titles, brand names, model numbers, or other proper nouns — keep them exactly as written. Here it's a term "Artist proof" not a proper noun; it's a general term in art prints. We should translate. So "Artist proof" -> "Prova de artista" or "Prova de artista" more common "Prova do artista" or "Artist's proof" in Portuguese is "Prova do artista" or "Prova do artista". Let's choose "Prova do artista". Preserve line breaks; there is a single line "Artist proof". So output: Prova do artista