Serena Williams of the U.S. serves during her first round match against Italy's Camila Giorgi at the Australian Open tennis tournament at Melbourne Park, Australia, January 18, 2016. (Photo by Jason O'Brien/Reuters)

In this photo taken on Wednesday, February 17, 2016, a volunteer fighter with the Syrian Government forces sits atop a tank in the province of Raqqa, Syria. In recent weeks, Syrian government forces captured dozens of villages and towns across the country. (Photo by Alexander Kots/Komsomolskaya Pravda via AP Photo)

Dancer Chachi Gonzalez arrives at Nickelodeon's 2016 Kids' Choice Awards in Inglewood, California March 12, 2016. (Photo by Mario Anzuoni/Reuters)

A woman cries after a supporter of opposition leader Raila Odinga was killed by police, witnesses said, in Mathare slum in Nairobi, Kenya August 9, 2017. (Photo by Goran Tomasevic/Reuters)

Chloe Ferry attends the Geordie Shore series 15 “Shag Pad on Tour” cast launch at Tower Bridge on August 16, 2017 in London, England. (Photo by Karwai Tang/WireImage)

Sepak Takraw, ISTAF Super Series Finals Thailand 2014/2015, Nakhon Pathom Municipal Gymnasium, Huyjorake Maung, Nakonprathom, Thailand on October 20, 2015: Thailand's Sudaporn Palang in action during the group stage. (Photo by Asia Sports Ventures/Action Images via Reuters)

The world-famous sprinter Usain Bolt, 30, took a break from the track to celebrate Carnival as revellers doused each other with paint in Trinidad and Tobago on February 26, 2017. (Photo by David Wears/Splash News and Pictures)

An AH-64D Apache attack helicopter flies in front of a wall of fire during the South Carolina National Guard Air and Ground Expo at McEntire Joint National Guard Base, South Carolina, U.S. on May 6, 2017. (Photo by Jorge Intriago/Reuters/Courtesy Air National Guard)