Okay, the user wants me to translate "piano keys" into Japanese. Let me think. The direct translation would be "ピアノの鍵盤" which is the standard term for piano keys in Japanese. I should check if there's any alternative term, but I don't think so. Since the original content isn't in Japanese, I need to provide the translation. The user specified to output only the translation without any explanations, so I'll just write "ピアノの鍵盤" as the response.