Robby's URL didn't bring up any lyrics for me.

However, the proper title of the song is "Cuanto Le Gusta", not "La". According to the following page, the song was performed in the 1948 movie "A Date with Judy" by Carmen Miranda with Xavier Cugat And His Orchestra: http://www.rhino.com/features/tracks/72722trx.html

Here's a page about "Flying Down to Rio" (RKO, 1933), with no mention of Carmen Miranda or the song; however, it does mention "The Carioca", the song that Fred Astaire and Ginger Rogers danced to – their first dance pairing on-screen (and the rest is history!): http://www.reelclassics.com/Teams/Fred&Ginger/fred&ginger1.htm