Servicewomen march in formation during a Victory Day military parade marking the 74th anniversary of the victory over Nazi Germany in the 1941-1945 Great Patriotic War, the Eastern Front of World War II, in Moscow's Red Square, Russia on May 9, 2019. (Photo by Valery Sharifulin/TASS)

A man walks by as tourists take selfies on the French Riviera city of Nice on June 24, 2019, as temperatures soar to 33 degrees Celsius. Forecasters say Europeans will feel sizzling heat this week with temperatures soaring as high as 40 degrees Celsius (104 degrees Fahrenheit) in an “unprecedented” June heatwave hitting much of Western Europe. (Photo by Valery Hache/AFP Photo)

Dario Sammartino, of Italy, competes at the final table during the World Series of Poker at the Rio hotel-casino in Las Vegas Sunday, July 14, 2019. (Photo by Steve Marcus/Las Vegas Sun via AP Photo)

A “caixer” (horse rider) rears up on his horse surrounded by a cheering crowd during the traditional “Jaleo” at the Sant Antoni Festival in Es Castell, Balearic Islands, Spain on July 27, 2019. (Photo by Matthias Oesterle/Zuma Press/Picturedesk.com)

Students, dressed in a whole array of fancy dress outfits, were pictured on a wild night out to kick off Freshers' Week in Leeds, England on September 21, 2019. Freshers' Week is a period before the start of an academic year at a university or tertiary institutions. During this period, students participate in a wide range of social activities. (Photo by N B (PRESS) LTD)

A Beijing Opera performer dances for a show by designer Hao Weimin at China Fashion Week, China, October 28, 2019. (Photo by Jason Lee/Reuters)

French aircrafts of the Patrouille de France spray colored smoke during a performance on the opening day of the Dubai Airshow in Dubai, United Arab Emirates, Sunday, November 17, 2019. (Photo by Kamran Jebreili/AP Photo)

A student falls asleep as she holds a book containing a portrait of China's late chairman Mao Zedong during a lesson at the Democracy Elementary and Middle School in Sitong town, Henan province December 3, 2013. In a remote part of central China, the day starts at the Democracy Elementary and Middle School with a pre-dawn jog, some revolutionary songs and then an activity long since forgotten at other schools: reciting quotations from Mao Zedong's famed “Little Red Book”. While the ruling Communist Party that Mao led continues to hold him in esteem as the leader of the Communist Revolution, his radical policies and teachings have been largely shelved since his death in 1976 in favour of a pro-market approach that has turned China from a backwater into the world's second biggest economy. The 120th anniversary of Mao's birth is on December 26, 2013. (Photo by Carlos Barria/Reuters)