Problem: Edward Leo Peter McMahon Jr. (March 6, 1923 - June 23, 2009) was an American announcer, game show host, comedian, actor and singer. McMahon and Johnny Carson began their long association in their first TV series, the ABC game show Who Do You Trust?, running from 1957 to 1962. Then afterwards, McMahon would make his famous thirty-year mark as Carson's sidekick, announcer and second banana on NBC's highly successfully The Tonight Show Starring Johnny Carson from 1962 to 1992.

The pair joined The Tonight Show Starring Johnny Carson on October 1, 1962 on NBC. He describes what happened when the pair first met, the whole meeting being "... about as exciting as watching a traffic light change". For almost 30 years, McMahon introduced the show with a drawn-out "Heeere's Johnny!" His booming voice and constant laughter alongside the "King of Late Night" earned McMahon the nickname the "Human Laugh Track" and "Toymaker to the King". As part of the introductory patter to The Tonight Show, McMahon would state his name out loud, pronouncing it as , but neither long-time cohort Carson nor anyone else who interviewed him ever seemed to pick up on that subtlety, usually pronouncing his name .  Aside from his co-hosting duties, it also fell upon McMahon during the early years of Carson's tenure (when the show ran 105 minutes) to host the first fifteen minutes of Tonight, which did not air nationally. McMahon also served as guest host on at least one occasion, substituting for Carson during a week of programs that aired between July 29 and August 2, 1963, and again for two nights in October 1963. McMahon served as a counter to the notoriously shy Carson. Nonetheless, McMahon once told an interviewer that after his many decades as an emcee, he would still get "butterflies" in his stomach every time he would walk onto a stage and would use that nervousness as a source of energy.  His famous opening line, "Heeere's Johnny!", was used in the 1980 horror film The Shining by the character Jack Torrance (played by Jack Nicholson) as he goes after his wife and child with an axe. He did in-program commercials for many sponsors of The Tonight Show, most notably Budweiser beer and Alpo dog food, and also did commercials for them that ran on other programs.

What caused McMahon to leave The Tonight Show?

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Question:
Audra Ann McDonald (born July 3, 1970) is an American actress and singer. Primarily known for her work on the Broadway stage, she has won six Tony Awards, more performance wins than any other actor, and is the only person to win all four acting categories. She has performed in musicals, operas, and dramas such as A Moon for the Misbegotten, 110 in the Shade, Carousel, Ragtime, Master Class and Porgy and Bess. As a classical soprano, she has performed in staged operas with the Houston Grand Opera and the Los Angeles Opera and in concerts with symphony orchestras like the Berlin Philharmonic and New York Philharmonic.
McDonald played Billie Holiday on Broadway in the play Lady Day at Emerson's Bar and Grill in a limited engagement that ended on August 10, 2014. After previews that began on March 25, 2014, the play opened at the Circle in the Square Theatre on April 13, 2014. Of the play, McDonald said in an interview:  It's about a woman trying to get through a concert performance, which I know something about, and she's doing it at a time when her liver was pickled and she was still doing heroin regularly...I might have been a little judgmental about Billie Holiday early on in my life, but what I've come to admire most about her - and what is fascinating in this show - is that there is never any self-pity. She's almost laughing at how horrible her life has been. I don't think she sees herself as a victim. And she feels an incredible connection to her music - she can't sing a song if she doesn't have some emotional connection to it, which I really understand.  McDonald won the Tony Award for Best Performance by an Actress in a Leading Role in a Play for this role, making her the first person to earn six Tony Award wins for acting (not counting honorary awards) and the first person to win a Tony Award in all four acting categories. In her acceptance speech, "she thanked her parents for encouraging her to pursue her interests as a child." She also thanked the "strong and brave and courageous" African-American women who came before her, saying in part, "I am standing on Lena Horne's shoulders. I am standing on Maya Angelou's shoulders. I am standing on Diahann Carroll and Ruby Dee, and most of all, Billie Holiday. You deserved so much more than you were given when you were on this planet. This is for you, Billie."  This performance was filmed at Cafe Brasil in New Orleans and broadcast on HBO on March 12, 2016. McDonald received a 2016 Emmy Award nomination for Outstanding Lead Actress in a Limited Series or Movie for her role in the broadcast.  McDonald had planned to make her West End debut as Holiday in Lady Day in June through September 2016, but after becoming pregnant she postponed these plans. She performed in Lady Day in June 2017 through September 9, 2017, at the Wyndham's Theatre in the West End.
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regularly...I might have been a little judgmental about Billie Holiday early on in my life, but what I've come to admire most about her