A policeman reacts during a clash with protestors during a protest against the proposed changes to France's working week and layoff practices, in Lyon, central France, Thursday, April 28, 2016. French protesters are back on the streets over proposed reforms to the country's labor rules and strikers have forced cancellations and delays at two airports serving Paris. (Photo by Laurent Cipriani/AP Photo)

A Kenyan Red Cross personnel and a volunteer console a relative of a victim, at the site of a building collapse in Nairobi, Kenya, Saturday, April 30, 2016. A six-story residential building in a low income area of the Kenyan capital collapsed Friday night under heavy rain and flooding, killing at least seven people and injuring over 100 others, Kenyan officials said. (Photo by Sayyid Abdul Azim/AP Photo)

Heather Larsen from Golden, Colorado, USA performs a split while walking the slackfline or highline across two towers in the Tower of David citadel complex overlooking the Old City of Jerusalem 02 May 2016. Larsen is one of the world's top female highliners, or slack liners and walked the lines as part of a Kickstarter campaign for an outdoor product. The tower at left was built by King King Herod some 2000 years ago. (Photo by Jim Hollander/EPA)

A pair of tigers soak in a shallow pool at Tiger Temple, a Buddhist monastery where paying visitors can interact with young adult tigers, in Kanchanaburi, Thailand, March 16, 2016. The attraction, near the Myanmar border, started collecting the animals 15 years ago when villagers brought an injured tiger cub to the local abbot, who agreed to care for it. Today there are nearly 150 tigers at the monastery. (Photo by Amanda Mustard/The New York Times)

A woman takes part in a global March for marijuana in Medellin, Colombia, May 7, 2016. The Global Marijuana March (GMM) is an annual rally held at different locations across the planet. It refers to cannabis-related events that occur on the first Saturday in May, or thereabouts, and may include marches, meetings, rallies, raves, concerts, festivals and information tables. (Photo by Fredy Builes/Reuters)

Four pillars of light from the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) are shown reaching into the Chilean night sky in this image from ESO Photo Ambassador Fred Kamphues, on September 2, 2016. The lasers are a key part of the adaptive optics system on the VLT. Adaptive optics allows astronomers to drastically reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT. (Photo by F. Kamphues/ESO)

This photo taken on June 19, 2017 shows Indian yoga teacher Mahesh Yogiji attempting a world record for the longest yoga session in Ahmedabad, ahead of International Yoga Day on June 21. According to Guiness World Records, the longest yoga marathon undertaken by a man lasted 69 hours and was achieved by V Gunasekaran in Tamil Nadu in June 2016. (Photo by Sam Panthaky/AFP Photo)

Young people jump over a bonfire as they take part in the Ivan Kupala Night celebration, a traditional Slavic holiday, outside the small town of Turov, some 270 km south of Minsk, on July 6, 2016. People celebrate Kupala Night with bonfires that last throughout the night with some leaping over the flames as it is believed that the act of jumping over the bonfire cleanses people of illness and bad luck. (Photo by Sergei Gapon/AFP Photo)