A U.S. Army B-24 Liberator Bomber is hailed by a ground crewman as it takes off over a line of shark- nosed fighter planes at an advanced base in China on a mission on October 10, 1943, to bomb Japanese installations. (Photo by AP Photo)

Vladimir Putin looks at a model of the Tupolev TU-160 bomber, or Blackjack, that was presented to him on his arrival in Olenegorsk, Russia, August 16, 2005. Putin flew in the Tupolev TU-160 bomber and took part in the launch of cruise missiles in the Arctic north. (Photo by Reuters/ITAR-TASS/Presidential Press Service)

Attendees wear a cardboard “Facebox” at the 2017 South By Southwest (SXSW) Interactive Festival at the Austin Convention Center in Austin, Texas, U.S., on Monday, March 13, 2017. The SXSW Interactive Festival features a variety of tracks that allow attendees to explore what's next in the worlds of entertainment, culture, and technology. (Photo by David Paul Morris/Bloomberg)

A common kingfisher sits on a branch of a tree after catching an insect in Allahabad, India, Sunday, July 9, 2017. The common kingfisher is a highly territorial bird that has to eat nearly sixty percent of its bodyweight every day. (Photo by Rajesh Kumar Singh/AP Photo)

A vendor decorates a sacrificial camel ahead of the Eid al-Adha festival, in Karachi, Pakistan, 23 August 2016. Eid al-Adha is the holiest of the two Muslims holidays celebrated each year, with this year will be celebrated on 02nd September. Eid al-Adha marks the yearly Muslim pilgrimage (Hajj) to visit Mecca, the holiest place in Islam. Muslims slaughter a sacrificial animal and split the meat into three parts, one for the family, one for friends and relatives, and one for the poor and needy. (Photo by Rehan Khan/EPA)

Greece's Stefanos Tsitsipas falls after diving to return a shot against Switzerland's Stan Wawrinka during their fourth round match of the French Open tennis tournament at the Roland Garros stadium in Paris, Sunday, June 2, 2019. (Photo by Christophe Ena/AP Photo)

A pro-government supporter scuffles with an anti-extradition supporter outside the office of pro-China lawmaker Junius Ho in Tsuen Wan in Hong Kong, China on July 22, 2019. Hong Kong demonstrators gathered for another weekend of protests against the controversial extradition bill and with a growing list of grievances, maintaining pressure on Chief Executive Carrie Lam. (Photo by Edgar Su/Reuters)

A man walks on the road between Nouahibou and Nouakchott, where three Spanish aid workers were abducted in Mauritania, December 3, 2009. (Photo by Rafael Marchante/Reuters)