Singer John Mayer introduced some levity to the ongoing coronavirus pandemic while taking a lighthearted jab at the celebrities who sang John Lennon’s “Imagine” on social media last week. The 42-year-old singer took to Instagram to share a mini-episode of his “Current Mood” series in which he jokingly explained that he was asked by “Wonder Woman” star Gal Gadot to be a part of her mashup of people singing the song.