What was one famous piece of music that Lady Gaga wrote?

Lady Gaga has written and co-written many famous pieces of music, including:

* "Just Dance" (2008)

* "Poker Face" (2008)

* "Bad Romance" (2009)

* "Telephone" (2010)

* "Born This Way" (2011)

* "Applause" (2013)

* "Perfect Illusion" (2016)

* "Million Reasons" (2016)

* "Shallow" (2018, from the film "A Star Is Born")