Meghan Trainor was transformed into a cartoon character and wrote a song for 'The Peanuts Movie' soundtrack

Meghan Trainor just teamed up with the cast of "The Peanuts Movie" and is helping spread a little confidence through some song and dance.

The 21-year-old recorded a song called "Better When I'm Dancin'" for the new "Peanuts" movie soundtrack and it's all about confidence. The creators wanted a song about confidence and they felt Trainor would be a perfect fit ... and for good reason. The "All About That Bass" singer has been spreading self-love ever since her breakthrough back in 2014. Since then, she's been motivating confidence via way of her MTrain Tour across the U.S. and Canada.

According to People.com, Trainor was inspired to write the song through dancing on stage and having fun, which provide her the confidence she needs to take on the day. She also revealed her favorite "Peanuts" character is Sally Brown. Take a look at Trainor's character.

She's also been performing the new song on her MTrain Tour.

"The Peanuts Movie" hits theaters Nov. 6, 2015.

Click through for photos of Meghan Trainor:

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