A wrestler from the Nuba Mountains tribe is seen during a celebration of their cultural heritage, as part of ongoing events to commemorate the International Day of the World's Indigenous Peoples, in Omdurman August 15, 2015. The International Day of the World's Indigenous Peoples is observed on August 9 annually. (Photo by Mohamed Nureldin Abdallah/Reuters)

Music student Daniele Gonzalez, (centre row, L), and Australian musician Susie Park from the Minnesota Orchestra (centre row, 2nd L), react during a rehearsal in Havana, May 15, 2015. The Minnesota Orchestra will offer two concerts in Havana and is the first major U.S. orchestra to play in Cuba since 1999. The trip cost nearly $1 million. It was underwritten by Marilyn Carlson Nelson, an heir to the Carlson hotel company fortune, and her husband Glen. The U.S. government gave special permission for a direct charter flight from Minneapolis to Havana for the event, putting 4 tons of equipment and 160 people on an Airbus 330. (Photo by Alexandre Meneghini/Reuters)

Dancers take part in the Karneval der Kulturen (Carnival of Cultures) street parade of ethnic minorities, in Berlin, Germany, May 24, 2015. A few dozen dancers, musicians and performers from dozens of communities took part in the urban festival on Sunday that aspires to reflect the multi-ethnic diversity of the German capital. (Photo by Hannibal Hanschke/Reuters)

A woman shoots her rifle at a forest shooting range near the village of Visnova, Czech Republic, June 9, 2016. (Photo by David W. Cerny/Reuters)

A lady smiles during the annual Calabar cultural festival in Calabar, Nigeria, December 28, 2015. Picture taken December 28, 2015. (Photo by Reuters/Stringer)

Actor Cornelius Obonya as Jedermann and actress Brigitte Hobmeier as Buhlschaft perform on stage during a dress rehearsal of Hugo von Hofmannsthal's drama “Jedermann” (Everyman) at Domplatz square in Salzburg, Austria, July 16, 2015. The play is directed by Julian Crouch and Brian Mertes and will premiere as part of the annual Salzburg cultural Festival on July 19, 2015. (Photo by Leonhard Foeger/Reuters)

A Russian-made rifle, carried by this woman when she was captured in Nearby Brush, is slung around her neck by South Vietnamese soldiers before they began their interrogation of her as Viet Cong suspect near AP La Ghi in Vietnam, August 25, 1965. The girl behind the woman, also was captured in the brush. (Photo by AP Photo)

U.S. Army helicopters providing support for U.S. ground troops fly into a staging area fifty miles northeast of Saigon, Vietnam, August 28, 1966. Helicopter fuel is stored in the large rubber tanks, foreground. (Photo by Henri Huet/AP Photo)