A Ukrainian serviceman wearing a new year's hat waves at his comrades while standing beside his tank near Debaltseve, eastern Ukraine, February 8, 2015. (Photo by Gleb Garanich/Reuters)

A tourist reacts as an elephant sprays her with water in celebration of the Songkran water festival in Thailand's Ayutthaya province, April 9, 2014. Songkran, the most celebrated festival of the year, marks the start of Thailand's traditional New Year. (Photo by Chaiwat Subprasom/Reuters)

To mark Halloween, 150 teens descended upon a swimming pool in Essex to help mobile network giffgaff recreate the famous Tomatina tomato fight... only this time, with blood and guts. Different takes #giffgaffguts. On October 18, 2013 in Dagenham, England. (Photo by Dave J. Hogan/Stringer for giffgaff)

In this Wednesday, March, 5, 2014 photo, Afghan female boxers practice at the Kabul Stadium boxing club, Afghanistan. The women, who are 18 and older, don't have much more than determination, and a trainer who runs them through their paces, watches as they spar, corrects their technique, tells them when to jab, how to protect themselves, when to power through with a left and then a right. (Photo by Massoud Hossaini/AP Photo)

A stray puppy walks along abandoned train tracks near the Chernobyl nuclear power plant on August 19, 2017 near Chornobyl, Ukraine. An estimated 900 stray dogs live in the exclusion zone, many of them likely the descendants of dogs left behind following the mass evacuation of residents in the aftermath of the 1986 nuclear disaster at Chernobyl. (Photo by Sean Gallup/Getty Images)

A man eats in front of his Basset Hounds during the first day of the Crufts Dog Show in Birmingham, Britain March 9, 2017. (Photo by Darren Staples/Reuters)

A German Shepard bares its teeth during Schutzhund attack dog training at Witmer-Tyson Imports February 14, 2002 in Newark, CA. (Photo by Justin Sullivan/Getty Images)

Beluga the bog poses as Britney Spears during the 17th annual Tompkins Square Halloween Dog Parade October 28, 2007 in New York City. The event is the largest dog Halloween party in the United States with an annual attendance of over 400 costumed dogs. (Photo by Mario Tama/Getty Images)