Who had his first lead role in the film "The Jerk" from 1979?

Explanation

Steve Martin (born 1945) is an American actor, comedian, playwright and producer. He is particularly well known for his role as a comedian in several family films. He started his career as an entertainer at children's parties, before breaking through as a stand-up comedian. He has also written the script for several of his films. Big Steve Martin hits include "The Jerk" (1979), "Roxanne" (1987) and "Parenthood" (1989).