Students celebrate their A-level results at King Edward VI High School for Girls in Birmingham, England on August 18, 2016. The proportion of top grades achieved by A-level students across the UK has fallen for a fifth year in a row, and girls have caught up with boys in attaining A* grades. (Photo by Joe Giddens/PA Wire)

A hot air balloon in tortoise shape flies in the air during the Tazaungdaing air balloon festival in Pyin Oo Lwin, Myanmar, 25 November 2015. During the festival, hot air balloons made of multicolored papers and hung with paper lanterns, fireworks and fire sticks are exploded in mid-air. (Photo by Hein Htet/EPA)

A pilot looks up from a U.S. F-22 Raptor fighter as it prepares to refuel in mid-air with a KC-135 refuelling plane over European airspace during a flight to Britain from Mihail Kogalniceanu air base in Romania April 25, 2016. (Photo by Toby Melville/Reuters)

A Vietnamese cosplayer poses as police officer character from the game during the League of Legends (LOL) Mid-Season Invitational 2019 play-in group stage, in GG Stadium, Ho Chi Minh, Vietnam May 5, 2019. (Photo by Reuters/Kham)

Wearing a mariachi hat, candidate Clara Brugada, who is running as a delegation leader under the ruling party Morena, smiles as she greets supporters on the last day of campaigning ahead of the June 6 mid-term elections, in the Iztapalapa borough of Mexico City, Wednesday, June 2, 2021. (Photo by Marco Ugarte/AP Photo)

The waning moon sets behind leafless sumac trees on a crisp, clear morning, Thursday, December 15, 2016, in Portland, Maine. Much of the northern Mid-Atlantic and Northeast will stay cold for the next couple of days as the arctic air remains stuck over the northern Appalachians, the National Weather Service said. (Photo by Robert F. Bukaty/AP Photo)

American actress and model Christina Hendricks attends NBC's New York Mid Season Press Junket at Four Seasons Hotel New York on January 24, 2019 in New York City. (Photo by Jamie McCarthy/Getty Images)

Pilots plan a flight manoeuvre with model aircraft at a military air base in Vasylkiv, Ukraine, August 3, 2016. (Photo by Gleb Garanich/Reuters)