Giant Panda Mei Xiang plays in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Giant Panda Mei Xiang eats treats in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Visitors watch a giant panda in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Giant Panda Mei Xiang plays in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Bei Bei, a three-year-old giant panda, plays in the David M. Rubenstein Family Giant Panda Habitat at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Giant Panda Mei Xiang eats treats in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Giant Panda Mei Xiang eats treats in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Giant Panda Mei Xiang eats treats in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)
Giant Panda Mei Xiang eats treats in the giant panda house at the Smithsonian's National Zoo in Washington D.C., the United States, on Feb. 23, 2019. The Smithsonian's National Zoo in Washington D.C. held a housewarming event inside the giant panda house on Saturday to celebrate the completion of a new visitor exhibit. (Xinhua/Ting Shen)