Actually, it was from “Iolanthe”, which was very popular in its time but not as popular now (like Pirates of Penzance, HMS Pinafore, and The Mikado)
Iolanthe was a fairy who married a mortal and complicated matters by having a half-fairy, half-mortal son. The son falls in love with a mortal girl who is about to be wed to a Member of the House of lords, and the fairies take over the Parliament!
(((((I wonder if WS Gilbert was hinting that there were fairies in Parliament?))))))
It was my favorite when i was a kid! :-)
Lord Chancellor’s Nightmare Song
https://www.youtube.com/watch?v=tuWTNLdKSOs