Lady, Play Your Mandolin! Is part of the Merrie Melodies series, and is best known for the debut of Foxy, a fox who only appeared in this and two other shorts before being discontinued due to a phone call to Walt Disney demanding Warner Bros. Stop using the character due to his similarities to Mickey Mouse (as the short was made by an ex-Disney employee).
In this short, set to the song with the same name as the title (at the time, Merrie Melodies was done to promote songs Warners owns), Foxy arrives at a bar disguised at a Mexican saloon (which is pretty bold for Warner Bros., as this was two years before Prohibition was repealed). As a result of the era, the booze is labelled with skull and crossbones, and the characters all drink like crazy while singing the song. Even Foxy takes part in the singing and drinking, and even falling in love with a female vixen (later given the name Roxy) who actually plays her mandolin. A old short worth checking out if you treat it as the product of its time.