Brazilian graffiti artist Eduardo Kobra (C) puts the final touches to his piece of art in tribute to Brazilian architect Oscar Niemeyer, next to his assistants, at the financial center on Sao Paulo's Avenida Paulista January 22, 2013. Kobra created the 56-metre (61-yard) tall graffiti artwork as a tribute to Niemeyer, one of the 20th century's most influential modernist architects. Niemeyer died in December 2012, aged 104. (Photo by Andre Penner/AP Photo)

Detail of a sand sculpture of Pirates of the Caribbean is seen as pieces are prepared as part of this year's Hollywood themed annual Weston-super-Mare Sand Sculpture festival on March 26, 2013 in Weston-Super-Mare, England. Due to open on Good Friday, currently twenty award winning sand sculptors from across the globe are working to create sand sculptures including Harry Potter, Marilyn Monroe and characters from the Star Wars films as part of the town's very own movie themed festival on the beach. (Photo by Matt Cardy)

Estonia's olympic team female marathon runners triplets (L-R) Lily, Liina and Leila Luik run during a training session in Tartu, Estonia, May 26, 2016. Leila, Liina and Lily Luik will make Olympics history as the first identical triplets to compete against each other when they cross the start line for the women's marathon in Rio. (Photo by Ints Kalnins/Reuters)

Somali government soldiers hold their positions during gunfire after a suicide bomb attack outside Nasahablood hotel in Somalia's capital Mogadishu, June 25, 2016. Somalia's al Shabaab Islamist group launched a suicide bomb attack on a hotel in the center of Mogadishu on Saturday before fighters stormed inside, police and the militant group said. Police said at least 15 people had died, including guards at the site, civilians and militants. Others were wounded. (Photo by Feisal Omar/Reuters)

Rooftops of solar powered houses are pictured in Ota, 80 km northwest of Tokyo in this October 28, 2008 file photo. One by one, Japan is turning off the lights at the giant oil-fired power plants that propelled it to the ranks of the world's top industrialised nations. With nuclear power in the doldrums after the Fukushima disaster, it's solar energy that is becoming the alternative. Solar power is set to become profitable in Japan as early as this quarter, according to the Japan Renewable Energy Foundation (JREF), freeing it from the need for government subsidies and making it the last of the G7 economies where the technology has become economically viable. (Photo by Yuriko Nakao/Reuters)

In this Monday, October 5, 2015 photo, a thick blanket of early morning fog partially shrouds the skyscrapers of the Marina and Jumeirah Lake Towers districts of Dubai, United Arab Emirates. Dubai's rapid transformation from a desert outpost into one of the world's most architecturally stunning cities is mapped out in the Marina. Where just 15 years ago there was empty, flat land, today a bustling neighborhood thrives centered around a canal and an impressive skyline that pierces through the clouds. (Photo by Kamran Jebreili/AP Photo)

Humboldt Penguins swim in their pool as a keeper looks on through a spherical window during the annual stocktake press preview at London Zoo in Regents Park in London Monday, January 4, 2016. A requirement of ZSL London Zoo's license, the annual audit takes keepers a week to complete and all of the information is shared with zoos around the world via the International Species Information System, where it's used to manage the worldwide breeding programmes for endangered animals. (Photo by Alastair Grant/AP Photo)

A Kurdish girl wears her relative's assault rifle and ammunition belt as she waits at the Iraqi Kurdish Shaqouli checkpoint, some 35 kilometres east of Mosul, on November 10, 2016. Since the start of the Mosul offensive the Kurds have moved their border some 10 kms closer to Iraq's second city, marking it out with a line in the sand. (Photo by Odd Andersen/AFP Photo)