Tokyo resident Ken Yokochi plays accordion. The song is Tama-Chan Snoa by Lars Hollmer. Some detail on how accordions work:
The instrument is played by compressing or expanding the bellows whilst pressing buttons or keys, causing valves, called pallets, to open, which allow air to flow across strips of brass or steel, called reeds, that vibrate to produce sound inside the body.
Here’s another example of accordion music (Astrid’s Waltz) played on a Castagnari accordion:
The company has a photo gallery of an accordion being made… a wee bit fancier than the one we have. In the archives: more accordions.