who wrote it?
Dr. Luke
Party in the U.S.A.
Dr. Luke
put your hands up party in the usa It  is a song.
wiki:7095192
Party in the U.S.A. [SEP] Introduction
"Party in the U.S.A." is a song by American singer Miley Cyrus for her first extended play (EP) "The Time of Our Lives" (2009). It was released on August 11, 2009, by Hollywood Records as the lead single from the project. The song was written and produced by Dr. Luke, with additional songwriting provided by Jessie J and Claude Kelly. "Party in the U.S.A." was originally intended for Jessie J, but after deciding it was not edgy enough for her, they passed it to Cyrus and adjusted the lyrics to fit her persona. Not completely identifying with "Party in the U.S.A.", Cyrus chose it for "The Time of Our Lives" partially due to a need for tracks.