A sewer cleaner of Dhaka City Corporation cleaning out the city's sewers on May 03, 2017 in Dhaka, Bangladesh. Despite a rise in the number of deaths of manhole workers every year, workers regularly go into the manholes without any protective gear. (Photo by Zakir Chowdhury/Barcroft Images)

Couples take part in a competition during a mass wedding of 64 doctoral student couples at Harbin Institute of Technology, a university in Harbin, Heilongjiang province, China, June 4, 2017. (Photo by Reuters/Stringer)

Fighters of the Popular Resistance Committees stand during a graduation ceremony of the affiliate special forces of the Popular Resistance, in Yemen's southwestern city of Taiz October 8, 2015. (Photo by Reuters/Stringer)

A man flies a kite on the Bund while buildings of Pudong's Lujiazui financial district stand across the Huangpu River as the sun rises in Shanghai, China, on Friday, October 2, 2015. (Photo by Qilai Shen/Bloomberg)

The Jet Propulsion Lab team's RoboSimian robot turns on a valve at a simulated disaster-response course during day one of the Defense Advanced Research Projects Agency (DARPA) Robotics Challenge finals in Pomona, California, June 5, 2015. (Photo by David McNew/Reuters)

(From L) Spanish actresses Aixa Villagran, Leticia Dolera and Celia Freijeiro pose on the pink carpet during the closing night of the 2019 Cannes International Series festival Canneseries, at the Palais des festival, in Cannes southern France, on April 10, 2019. (Photo by Valéry Hache/AFP Photo)

In this April 18, 2019 photo, tattoo artist Lalo Calva inks a tattoo on client Adrian Alonso Rodriguez, a journalist, announcer and dubbing artist, at the Corona Tattoo parlor in Mexico City. Not only inks and techniques have changed in Mexico over the years, but tattoos themselves have evolved from stigmatized symbols of gangs, violence and poverty to an art form. (Photo by Marco Ugarte/AP Photo)

Competitors take part in the annual Mud Madness event at Foymore Lodge on April 22, 2018 in Portadown, Northern Ireland. The adult version of the event includes two laps of an 8km course through 25 obstacles while the kids event is run over 2kms. The race is in it's eleventh year and is sponsored by McVities Jaffa Cakes and event charity partner Marie Curie together with other numerous charities and fundraising groups. (Photo by Charles McQuillan/Getty Images)