Passengers travel on the London train and underground system during the Christmas party season, December 18, 2015. (Photo by Paul Hackett/Reuters)

Visitors wear shirts with an image of former Chinese leader Mao Zedong at the Shanghai World Expo site in Shanghai, May 2, 2010. (Photo by Aly Song/Reuters)

A Vietnamese woman, wearing the traditional “ao dai” long dress, poses for photos along peach blossom flowers ahead of the Vietnamese “Tet” (Lunar New Year festival), in a field in Hanoi, Vietnam, February 2, 2016. (Photo by Reuters/Kham)

Developed for the British American Ambulance Corps, this new motorcycle ambulance is capable of speeding wounded soldiers 90 miles an hour from the front lines to field hospitals. Its springs are synchronized with the patient's heartbeat to avoid increasing fever when traveling over various Terrain. Viewing it in New York August 27, 1941, are left to right: constable Herbert Scott of England, driver; William E. Detlor, whose firm developed the vehicle; M. W. Stand, inspector-general of Civilian Defense, and Maj. Edward Riekert, also. (Photo by AP Photo)

A surfer dressed as Santa gets to his feet as he braves the cold seas and near flat waves during the annual Surfing Santa as part of the Santa Run and Surf 2016 at Fistral Beach in Newquay on December 4, 2016 in Cornwall, England. Now in its third year, the santa surf and fun run is organised by Fistral Surf Center and Cornwall Hospice Care and raises funds for local charities. (Photo by Matt Cardy/Getty Images)

In this picture taken on January 11, 2021, young gymnasts train at the Li Xiaoshuang Gymnastics School in Xiantao, Hubei province. This summer's delayed Tokyo Olympics, which are now due to start on July 23, 2021, will be the defining moment for Chinese gymnasts who have trained relentlessly since as young as age four in the pursuit of gold. (Photo by Nicolas Asfouri/AFP Photo)

This photograph taken on June 20, 2021 and received courtesy of Radchadawan Peungprasopporn via her Facebook account on June 22, 2021 shows an elephant searching for food in the kitchen of her home in Pa La-U, Hua Hin. (Photo by Radchadawan Peungprasopporn/Facebook via AFP Photo)

A handout photo made available by the Indian Air Force (IAF) showing an IAF helicopters during the rescue operation in flood affected areas of Dhanyaghari of Khanakul in West Bengal, India, 02 August 2021. According to the IAF, helicopters of Indian Air Force rescued 31 people from rooftops and brought them to safety to Arambaug. The helicopters also dropped emergency food supplies in the affected areas after the torrential rain in the state has thrown life out of gear and created flood like situation in many districts. (Photo by Indian Air Force/Handout via EPA/EFE)