Men cover their heads from the sun while riding on a motorcycle during a hot day in Cairo, Egypt, August 17, 2015. A heatwave killed at least 61 people across Egypt from Sunday to Tuesday and caused nearly 600 people to be admitted to hospital, Egypt's health ministry said on state news agency MENA on Wednesday. (Photo by Amr Abdallah Dalsh/Reuters)

The front wheels of a tractor, pulling a trailer overloaded with sugarcane, are seen lifted off the ground as it passes through the streets of Karor Lan Esan, Pakistan December 6, 2015. (Photo by Caren Firouz/Reuters)

A man makes traditional candy “Matang” in preparation for the upcoming Chinese Lunar New Year in Yuqing County, Zunyi, Guizhou Province, China, January 18, 2016. (Photo by Reuters/China Daily)

An Afghan boy plays in the ruins of a house that at one point belonged to the 13th-century Persian poet, Islamic scholar and Sufi mystic Jalal ad-Din Muhammad Rumi on the outskirts of Mazar-i-Sharif on November 25, 2015. (Photo by Farshad Usyan/AFP Photo)

Police officers display their AI-powered smart glasses in Luoyang, Henan province, China on April 4, 2018. (Photo by Reuters/China Stringer Network)

Blossoms and dust are blown by the wind as Jasmin Ricks, left, and her sister, Jessica Ricks, center, take in the cherry blossoms near the Tidal Basin in Washington on April 12, 2018. (Photo by Matt McClain/The Washington Post)

A man transports passengers on an improvised motorized rickshaw during heavy rains in Agartala, India, April 20, 2018. (Photo by Jayanta Dey/Reuters)

In this Thursday, June 14, 2018, file photo, students wear virtual reality goggles during a science class at Pyongyang Teachers' University, a teacher training college, in Pyongyang, North Korea. (Photo by Dita Alangkara/AP Photo)