Nothing Doing

https://commons.wikimedia.org/wiki/File:Groucho_Marx_A_Day_at_the_Races.jpg

Leo Rosten once received this note from Groucho Marx:

Dear Junior: Please excuse me for not answering your letter sooner. But I have been so busy not answering letters lately that I have not been able to get around to not answering yours in time. Love, Groucho.