Riot security forces clash with demonstrators as a motorcycle is set on fire during a protest against Venezuelan President Nicolas Maduro's government in San Cristobal, Venezuela May 29, 2017. (Photo by Carlos Eduardo Ramirez/Reuters)

Thai Princess Bajrakitiyabha (R) and Princess Sirivannavari Nariratana take part in the funeral procession for the late Thai king Bhumibol Adulyadej in Bangkok on October 26, 2017 A sea of black- clad mourners massed across Bangkok' s historic heart early on October 26 as funeral rituals began for King Bhumibol Adulyadej, a revered monarch whose passing after a seven- decade reign has left Thailand bereft of its only unifying figure. (Photo by Damir Sagolj/Reuters)

Sete Tamang, 20, avalanche survivor, waits to receive the bodies of his colleagues outside a morgue at Teaching Hospital in Katmandu, Nepal, Monday, October 20, 2014. Nepal was wrapping up rescue operations in its northern mountains Monday, saying all the hikers believed to have been stranded on a trekking route by a series of deadly blizzards are now safe. (Photo by Niranjan Shrestha/AP Photo)

M42 Subtle V1 cropped. One of the most well-known astronomical objects in our universe is the Orion Nebula and this image depicts the wider region of the Orion Molecular Cloud Complex that is its home. This complex also includes another popular target for astrophotographers, the Horsehead Nebula, as well as Barnard’s Loop and the Running Man Nebula, which can be seen to the left of this photograph. (Photo by Patrick Gilliland)

Blue, white and red brassieres, the colours of the French national flag, hang from a balcony in Marseille, France, November 27, 2015 as the French President called on all French citizens to hang the tricolour national flag from their windows on Friday to pay tribute to the victims of the Paris attacks during a national day of homage. (Photo by Jean-Paul Pelissier/Reuters)

A women wearing a mask to protect from extreme smog visits the Tiananmen Gate in Beijing December 8, 2015 as China's capital issues its first ever "red alert" for pollution. (Photo by Damir Sagolj/Reuters)

An Indian villager tries to tame a bull during a traditional bull-taming festival called “Jallikattu”, in the village of Palamedu, near Madurai, Tamil Nadu state, India, Monday, January 15, 2018. Jallikattu involves releasing a bull into a crowd of people who attempt to grab it and ride it. (Photo by R. Parthibhan/AP Photo)

Children of the Roma community play as they cool off in a fountain in the main square of Pristina, Kosovo on June 14, 2017. (Photo by Armend Nimani/AFP Photo)