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)

A child coughs as migrants and refugees run away after Macedonian police fired tear gas at hundreds of Iraqi and Syrian migrants who tried to break through the Greek border fence in Idomeni, on February 29, 2016. Greek police said more than 6,000 people were massed at the border, in a buildup triggered by Austria and Balkan states capping the numbers of migrants entering their territory. (Photo by Louisa Gouliamaki/AFP Photo)

UFC women's bantamweight champion Holly Holm and Miesha Tate face off during the UFC 196 weigh ins at the MGM Grand Garden Arena in Las Vegas on Friday, March 4, 2016. (Photo by L.E. Baskow/Las Vegas Sun via AP Photo)

A couple stands next to a poster depicting Dutch politician Geert Wilders and Russian President Vladimir Putin kissing, at a metro station in Amsterdam April 3, 2016. (Photo by Cris Toala Olivares/Reuters)

A competitor walks on tightrope during a performance in Taizhou, Zhejiang Province, China, May 7, 2016. (Photo by Reuters/China Daily)

Gigi Hadid and Emily Ratajkowski celebrated the opening of the shopping centre by taking part in the evening's ribbon cutting ceremony in Mykonos, Greece on June 30, 2018. (Photo by Richard Young/Rex Features/Shutterstock)

In this Wednesday, January 23, 2019, an anti-government protester covers her face with a Venezuelan flag, and uses toothpaste around her eyes to help lessen the effect of tear gas, during clashes with security forces after a rally demanding the resignation of President Nicolas Maduro in Caracas, Venezuela. The head of Venezuela's opposition-run congress declared himself interim president at the rally, until new elections can be called. (Photo by Fernando Llano/AP Photo)

A woman tries to catch snowflakes with her tongue during a snowfall on Chandragiri Hills in Kathmandu, Nepal on January 23, 2019. (Photo by Navesh Chitrakar/Reuters)