Staff of a boat restaurant on the Taedong River line up at the entrance as they wait to greet customers Sunday, June 18, 2017, in Pyongyang, North Korea. The boat is berthed along the river, which is the fifth longest river on the Korean Peninsula and runs through the country's capital, Pyongyang. (Photo by Wong Maye-E/AP Photo)

A young boy plugs his ears as his sister (C) and nanny (L) watch from Gravelly Point Park as planes land at Reagan National Airport in Arlington, Virginia on June 29, 2017. President Donald Trump' s travel ban on people from six mostly Muslim countries will come into force late Thursday, as controversy swirls over who qualifies for an exemption based on family ties. (Photo by Jim Watson/AFP Photo)

Passengers travel in an overcrowded train in the eastern Indian city of Patna, February 23, 2010. (Photo by Krishna Murari Kishan/Reuters)

A small section of the expanding remains of the Veil Nebula, a massive star that exploded about 8,000 years ago. The entire nebula is 110 light-years across, covering six full moons on the sky as seen from Earth, and resides about 2,100 light-years away in the constellation Cygnus, the Swan. (Photo by Reuters/NASA/ESA/Hubble)

Cambodian children sleep on a pavement at a park in Phnom Penh on July 8, 2016. (Photo by Tang Chhin Sothy/AFP Photo)

Syrian girls carry bags with bread as people queue up outisde a bakery in a rebel held neighbourhood in the northern city of Aleppo on July 12, 2016. Since mid-2012, Aleppo has been roughly divided between government control in the west and rebel control in the east, and has suffered enormous destruction in the war that has killed more than 280,000 people nationwide. Last week, a government advance brought regime troops within firing range of the Castello Road, the only remaining supply route into the opposition-held east, effectively severing rebel neighbourhoods from the outside world. With their route to the outside world cut, there is no new flour coming to the city's bakeries, and fuel to light their ovens is also now hard to find. (Photo by Karam Al-Masri/AFP Photo)

Men carry a dog, wearing a costume and seated on a stool, as a form of respect as they believe that dogs found water for their ancestors, during a local festival for the Miao ethnic minority in Jianhe county, Guizhou Province, China, August 14, 2016. (Photo by Reuters/China Daily)

An Indian artists uses sparkles to decorate statues of the Hindu god Lord Ganesh ahead of the forthcoming Ganesh Chaturthi festival at a workshop in Hyderabad on August 29, 2016. The statues are being prepared for the Ganesh Chaturthi festival a popular eleven-day long Hindu religious festival in India which will be celebrated from September 5 to 15. (Photo by Noah Seelam/AFP Photo)