A couple lights a lantern during a celebration, known as “Chaharshanbe Souri”, or Wednesday Feast, marking the eve of the last Wednesday of the solar Persian year, Tuesday, March 19, 2019, in Tehran, Iran. Iran's many woes briefly went up in smoke on Tuesday as Iranians observed a nearly 4,000-year-old Persian tradition known as the Festival of Fire. (Photo by Ebrahim Noroozi/AP Photo)

In this photo taken on Saturday, May 16, 2015, Snoek fish with salt on them after they were cleaned in Lambert's Bay, South Africa. The boats line up along the jetty, bobbing in the cold south Atlantic waters, bringing in the day's catch in the early afternoon. The long silver snoek fish is one of South Africa's traditional foods, and a main source of income for the town of Lambert's Bay. (Photo by Schalk van Zuydam/AP Photo)

A humanoid robot works side by side with employees in the assembly line at a factory of Glory Ltd., a manufacturer of automatic change dispensers, in Kazo, north of Tokyo, Japan, July 1, 2015. Japanese firms are ramping up spending on robotics and automation, responding at last to premier Shinzo Abe's efforts to stimulate the economy and end two decades of stagnation and deflation. (Photo by Issei Kato/Reuters)

A participant of the Castle Party festival poses for picture as a man walks past in Bolkow, southwestern Poland, July 16, 2015. The annual festival features around 50 musicians and artists playing on various stage Gothic rock and other styles of the dark music subculture. Outside Germany, it is one of the biggest festival with this genre of music, the event attracts regular international audience of up to 5000, the organizers said. (Photo by Kacper Pempel/Reuters)

Participants of the techno-parade “Zug der Liebe” (Train of love) dance on a street in Berlin, Germany July 25, 2015. The “Zug der Liebe” is the successor to the “Loveparade”, which in its heyday attracted up to 100,000 participants and ended in disaster and tragedy in 2010 when 21 people died and over 500 were injured due to suffocation from overcrowding at the “Loveparade” in Duisburg. (Photo by Axel Schmidt/Reuters)

A truck remains mired in mud and debris on State Route 58 near Tehachapi, California, about 60 miles (97 km) outside of Los Angeles October 17, 2015. A mudslide on Thursday left nearly 200 vehicles, including 75 semi-trailer trucks, stuck in up to five feet of mud, local sheriff's spokesman Ray Pruitt said. (Photo by David McNew/Reuters)

Residents cross a swelling dam, due to rising waters brought about by Typhoon Koppu, in Las Pinas city, metro Manila October 19, 2015. Powerful typhoon Koppu ploughed into the northeastern Philippines before dawn on Sunday destroying homes and displacing 10,000 people and whipping up coastal surges four meters (12 feet) high, disaster agency officials said. (Photo by Ezra Acayan/Reuters)

A young man, who says he is part of a local criminal gang, poses for a picture holding a gun in the neighbourhood of Korogcho in Nairobi, Kenya, March 19, 2015. Around 2 million people live in the shantytowns packed in around Kenya's capital. Crime is high amid chronic unemployment levels, while basic services and sanitation are scarce. Residents try to make the best of things, eking out a living and picking up work where they can. (Photo by Siegfried Modola/Reuters)