Lee Il-hyung is a South Korean film director and screenwriter. Prior to directing his first feature film "A Violent Prosecutor" (2016), Lee is an assistant director on films, such as "The Moonlight of Seoul" (2008), "My Way" (2011) and "" (2014), and commercial films. Using only the above description and what you know about the world, "Lee Il-hyung worked in the film industry for at least 8 years before directing his first feature film" is definitely correct, incorrect, or inconclusive? 