A junk boat sails in to dock as a woman sits on the pier in the central district of Hong Kong on May 15, 2019. (Photo by Isaac Lawrence/AFP Photo)

A competitor dressed up as Santa Claus jumps into the sea during the 102nd Barcelona Traditional Christmas Swimming Cup at the Old Harbour of Barcelona on December 25, 2011 in Barcelona, Spain. (Photo by David Ramos/Getty Images)

Robot couple Xiaolan (L) and Xiaotao carry trays of food at a restaurant in Jinhua, Zhejiang province, China, May 18, 2015. The restaurant, which opened on Monday, has two robots delivering food for customers. The robots were designed as a couple, Xiaolan and Xiaotao, according to local media. (Photo by Reuters/Stringer)

Iranian Shiite Muslim women gather around a bonfire after rubbing mud on their body during the “Kharrah Mali” (Mud Rubbing) ritual to mark the Ashura religious ceremony in the city of Khorramabad, some 470 kms southwest of Tehran, early in the morning on October 1, 2017. “Khrreh Mali” or “Mud Rubbing” is a ritual that is held in the city of Khorramabad every year to commemorate the seventh century slaying of Prophet Mohammed' s grandson Imam Hussein, in which Iranian men roll over in mud and dry themselves by gathering around the bonfires before flagellating themselves. (Photo by Atta Kenare/AFP Photo)

A decorated elephant march at the Navam Perahera, a Buddhist pageant of elephants, dancers and drummers, in Colombo February 3, 2015. Over 50 elephants participated in the street parade for Gangaramaya temple's annual Perahera festival, along with a nightly procession of traditional dancers, fire twirlers and traditional musicians. (Photo by Dinuka Liyanawatte/Reuters)

Revellers pose during the 24th Street Parade dance music event in Zurich, August 29, 2015. (Photo by Arnd Wiegmann/Reuters)

Girls play with live Teacup pigs, a rare pet in the country, at the start of celebrations leading to the Lunar New Year, Friday, February 1, 2019 at Lucky Chinatown Plaza mall in Manila, Philippines. The upcoming Year of the Pig represents abundance, diligence and generosity. (Photo by Bullit Marquez/AP Photo)

Drivers push cars to gas station during “oil crisis”, Roslindale, Boston, Massachusetts, 1973. (Photo by Spencer Grant/Getty Images)