Two years ago, Lyric Opera of Chicago presented what was called the world's first mariachi opera. It was well-received and a big hit with audiences--so much so that it spawned another mariachi opera. This time around it's a Lyric Opera commission that has brought back together the same creative team and many of the same performers from the previous work. Its title is El Pasado Nunca Se Termina or The Past Is Never Finished, and it's receiving its world premiere here in Chicago.