Then I Baidu what you said, "I have tried my best, I am perfect." "
All the results come from the same source, a book review written by one person.
For any comment, his answer is: I have tried my best, I am perfect. "This is the only source on the Internet.
There is no other source to prove that evelyn waugh himself said this.
I seriously doubt that evelyn waugh himself didn't have this famous saying, but the book reviewer created it himself.
I have done what I can. I have tried my best.