After several White House Correspondents’ Dinners, we all knew that former President Barack Obama had a killer deadpan. The new teaser trailer for the HBO limited series Life, Larry, and the Pursuit of Unhappiness puts that to the test, as Curb Your Enthusiasm star Larry David banters with “44” (Larry’s fun nickname) about making Obama his emergency contact. It’s not really a reflection of the series as a whole, which will be a sketch-driven look at American history through the singular lens of David and longtime collaborator Jeff Schaffer ( The League , Curb Your Enthusiasm ). It is, however, a taste of the dry wit to come from the HBO/Higher Ground comedy. According to the official logline for the series, “President and Mrs. Obama wanted to honor America’s 250th anniversary and celebrate the unique history of our nation on this special occasion.…