Tribesmen loyal to the Houthi movement perform the Baraa dance during a gathering to show support to the movement in Sanaa, Yemen, May 19, 2016. Bara or Baraa dance is one of the several traditional outdoor dances performed by men in the country of Yemen. Bara dance literally means a dagger dance, where each dancer holds a dagger. The style of the Bara dance differs from tribe to tribe. It is performed on special occasions. (Photo by Khaled Abdullah/Reuters)

Yang Shiguang, 77, performs stunts at a park in Xi'an, Shaanxi province, September 3, 2013. Yang has been a member of a stunt performance club since 2007, after retiring from a research institution. (Photo by Reuters/China Daily)

A snowboarder performs during the Red Bull Jump and Freeze competition at ski resort Shimbulak outside Almaty March 22, 2015. Participants wearing festive costumes perform tricks before getting into a pond with icy water. (Photo by Shamil Zhumatov/Reuters)

An actress performs in a puppet theater show at an UNRWA school in Burj al-Barajneh in Beirut May 14, 2015. The Arab Puppet Theatre Foundation (APTF) is touring the 68 schools of the UN refugee agency's UNRWA and performs for all 39,000 Palestinian students in Lebanon, in a project with UNICEF and UNRWA. (Photo by Mohamed Azakir/Reuters)

Ethnic Wa performer dressed as United Wa State Army (UWSA) soldiers perform a traditional dance in Mongmao, Wa territory in northeast Myanmar October 1, 2016. Wa State is an unrecognised state in Myanmar (Burma) and is currently subsumed under the official Wa Special Region 2 of northern Shan State. The Wa were once known as the “Wild Wa” by the British due to their practice of headhunting. (Photo by Soe Zeya Tun/Reuters)

A man performs ablution using water at an old fountain before performing prayers in the old city of Algiers Al Casbah, Algeria December 3, 2015. The Algiers Casbah is a UNESCO World heritage site that includes the Sidi Ramdane mosque and former fortress, 10 centuries old. Decay from the passing years, as well as earthquake damage in 2003, leads some to consider a move to modern apartments with financial backing from the government. Others refuse to leave a neighbourhood they have called home for decades. (Photo by Zohra Bensemra/Reuters)

A man dressed as a devil performs during a Krampus show in the southern Bohemian town of Kaplice, December 12, 2015. Each year people in traditional costumes and masks parade through the streets to perform an old ritual to disperse the ghosts of winter. (Photo by David W. Cerny/Reuters)

A man wearing a water-filled helmet in which a goldfish swims performs an act titled “Aquaman” during the Night Festival 2016 in Singapore, 20 August 2016. The ninth edition of the festival will run from 19 to 27 August and features installations and performances by a range of international and local artists. (Photo by Wallace Woon/EPA)