(CNN) Tig Notaro says she was "extremely" disappointed by a "Saturday Night Live" sketch that has drawn comparisons to her 2015 short film, "Clown Service."

On Saturday, host Louis C.K. starred in a sketch called "Birthday Clown" about a man who hired a clown for an uncomfortable one-on-one show.

Since its airing, Notaro said she's heard from a "cacophony of voices" who alerted her to the "potential plagiarizing" of her film.

In "Clown Service" Notaro plays a woman who enlists the services of a clown to bring her cheer in the midst of post-breakup blues.

The short film was written by Notaro and Melissa Blake and premiered at Vulture Festival in 2015.

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