Children wave Vietnamese and American flags while waiting for arrival of U.S. President Barack Obama (not pictured) before a welcoming ceremony at the Presidential Palace in Hanoi, Vietnam May 23, 2016. (Photo by Reuters/Kham)

Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, February 10, 2016. (Photo by B.K. Bangash/AP Photo)

A students with her face smeared in coloured powder, celebrates Holi at a university campus in Chandigarh, India March 23, 2016. (Photo by Ajay Verma/Reuters)

Indonesian mahouts (elephant masters) bathe elephants prior to a daily patrol at a Conservation Respons Unite (CRU) to control elephant-human conflicts in Serbajadi, East Aceh on April 7, 2016. Elephants have joined the front line in the fight against poaching and illegal logging in the dense jungles of Sumatra. Guided by their Indonesian mahouts, they trek alongside rivers, over rough terrain and deep into the rainforest in an area that is home to numerous endangered species, from orangutans to tigers, but which has suffered devastating deforestation in recent years. (Photo by AFP Photo/Januar)

DJ Evans Mireku Kissi (R) and fashion stylist Daniel Quist ride a motorcycle in front of a street side bar in Accra, Ghana. June 10, 2015. Young artists in Ghana's capital have evolved a new style that is turning heads and challenging accepted notions of African fashion. (Photo by Francis Kokoroko/Reuters)

Visitors wear shirts with an image of former Chinese leader Mao Zedong at the Shanghai World Expo site in Shanghai, May 2, 2010. (Photo by Aly Song/Reuters)

Lenka Tanner is pictured in Nottingham, United Kingdom on March 11, 2015. She starred in the Kuoni advert, Run on Water, advertising luxury holidays. She has set up her own synchronised swimming team called AquaStars. Tanner was born in Slovakia and starting synchronised swimming at the age of six. (Photo by Lucy Ray/The Guardian)

A girl carries utensils after filling them with water from a pipe that supplies water to trains at a railway station on the outskirts of Agartala, India, February 28, 2017. (Photo by Jayanta Dey/Reuters)