Here half the song is done done in a piano accompanied 'rehearsal' version:
Here is the whole thing:
When I sang in the Mikado the second time, playing the minor role of Pish Tush (the character who speaks at the beginning of the above clip); my brother, who was directing, was kind enough to write me into this song, sharing the lines with Pooh Bah.
I loved doing it; but couln't manage to do the tra la las as fast as necessary - so had to find a way to 'fake' them with traddle laddles instead...
See also: https://charltonteaching.blogspot.co.uk/search?q=mikado