A Romanian female soldier adjusts her helmet before taking part in weapons training with US Marines female counterparts at the Capu Midia Surface to Air Firing Range, on the Black Sea coast in Romania, Monday, March 20, 2017. About 1,200 US and Romanian troops take part in the Spring Storm 17 exercise, meant to simulate defense of the Romanian Black Sea coastline and urban areas. (Photo by Vadim Ghirda/AP Photo)

US President George W. Bush (R) and Russian President Vladimir Putin wave as the two presidents go for a ride in Putin's 1956 Volga before dinner 08 May 2005 at the his residence outside of Moscow. Bush hailed Russia's “bravery and sacrifice” in defeating Nazism, as he met Putin ahead of ceremonies marking the 60th anniversary of the end of World War II. Bush, who the previous day criticized the decades-long Soviet occupation of central Europe, said he was looking forward to the 09 May ceremony on Moscow's Red Square, to be attended by over 50 national leaders. (Photo by Tim Sloan/AFP Photo)

Filipino beauty candidates hide from the sun before a group photo during the media presentation of the Miss Philippines Earth 2017 held at a hotel in Manila, Philippines, 05 July 2017. A total of 40 environmentally aware and concerned Filipino young ladies will compete to represent the Philippines at the Miss Earth beauty pageant. Miss Earth is a pioneering beauty pageant that serves as a vehicle for environmental advocacy. (Photo by Mark R. Cristino/EPA)

High-wire artist Kane Petersen successfully walks a tightrope 300 metres above the ground at Eureka Skydeck on September 16, 2015 in Melbourne, Australia. The walk was the highest tightrope walk ever attempted in the Southern Hemisphere. The stunt is to mark the arrival of the film “The Walk” to Australian cinemas in October. The stunt saw Kane mimic the film's French high-wire artist Philippe Petit, who successfully walked between the twin towers of the World Trade Center in 1974. (Photo by Scott Barbour/Getty Images)

A man carries floats as he walks on an algae covered beach as a truck collecting algae passes by, along the coastline in Qingdao, Shandong province, July 6, 2015. (Photo by Reuters/China Daily)

Donald Ganslmeier, operator of the Motodrom, rides a motorbike inside the Motodrom during a press tour at Theresienwiese on the premises of the 182nd annual Oktoberfest in Munich, Germany, September 17, 2015. (Photo by Matthias Balk/EPA)

A dog wears fake eyes while riding a motorcycle in Samut Sakhon, Thailand June 23, 2016. (Photo by Jorge Silva/Reuters)

Robot couple Xiaolan (L) and Xiaotao carry trays of food at a restaurant in Jinhua, Zhejiang province, China, May 18, 2015. The restaurant, which opened on Monday, has two robots delivering food for customers. The robots were designed as a couple, Xiaolan and Xiaotao, according to local media. (Photo by Reuters/Stringer)