Walmart; Getty Images; Alyssa Powell/BIKoyaana Redstar, a luxury bag authenticator, has decades of experience identifying fake Hermès Birkin bags.She said that the viral "Walmart Birkin," or "Wirkin," has several telltale signs of being a dupe.But Walmart is also not trying to convince anybody that the Wirkin is the real deal, she added.This as-told-to essay is based on a conversation with Koyaana Redstar, the head of luxury buying at Luxe Du Jour, an online luxury boutique for vintage designer handbags.