Lululemon Athletica Inc. will open its first San Fernando Valley store at The Commons in Calabasas on April 6. The Canadian retailer, with 40 stores in the U.S., Australia and Japan, will offer complimentary weekly yoga classes and health seminars along with its selection of yoga and fitness apparel for men and women. The company said it chose the Calabasas location because of the area’s active lifestyle. The retailer will take a 2,212-square-foot store at the center, which is owned by Caruso Affiliated.