Nervous System included a second single which was co-written by which frequent writing partner?
Uh Huh (Julia Michaels song): "Uh Huh" is a song by American singer and songwriter Julia Michaels. Uh Huh (Julia Michaels song):  The song was written by Michaels and her frequent writing partner Justin Tranter, along with the song's producers, Mattias Larsson and Robin Fredriksson.
i don't know