A woman sits on a terrace at Tiki hostel in Cantagalo favela, in Rio de Janeiro, Brazil, April 16, 2016. Hostels in a few of Rio's more than 1,000 slums serve not only as a cheap housing alternative for the more adventurous among the estimated 500,000 foreign tourists expected to arrive for the Olympics in August. The establishments also open up the rich culture of the city's shantytowns for travellers, giving them a glimpse into once “no-go” areas where about one-fifth of Rio's population lives. (Photo by Pilar Olivares/Reuters)

A combination photograph shows revelers dressed in "Dia de Muertos" or "Day of the Dead" themes as they pose for photos while taking part in the Greenwich Village Halloween Parade in the Manhattan borough of New York October 31, 2015. (Photo by Carlo Allegri/Reuters)

Skulls placed on the floor are seen during a ceremony held for the "Dia de las natitas" (Day of the Skull) celebrations at the General Cemetery of La Paz, November 8, 2015. Bolivians, who keep close relatives skulls at home as a macabre talisman, flock to the cemetery chapel once a year to have the craniums blessed and to bring themselves good luck in the future. (Photo by David Mercado/Reuters)

A reveller wearing a demon costume takes part in the traditional festival of “Correfoc” in Palma de Mallorca, on January 17, 2015. The Correfoc is a night of revelry in which participants dress as demons and devils, and move through the streets scaring people with fire and fireworks. (Photo by Jaime Reina/AFP Photo)

Model Bella Hadid attends the “Cafe Society” premiere and the Opening Night Gala during the 69th annual Cannes Film Festival at the Palais des Festivals on May 11, 2016 in Cannes, France. (Photo by Tristan Fewings/Getty Images)

A girl looks at other children practicing on a boxing ring during an exercise session at a boxing school, in the Mare favela of Rio de Janeiro, Brazil, June 2, 2016. For many young residents the Luta Pela Paz (Fight For Peace) academy offers a glimpse of an alternative: a chance to build discipline and self-esteem through boxing and martial arts. (Photo by Nacho Doce/Reuters)

Brazil's synchronised swimmers Luisa Borges (front) and Maria Eduarda Miccuci perform during a training session at the Rio Olympic Park in Rio de Janeiro, Brazil, April 7, 2016. (Photo by Pilar Olivares/Reuters)

A machine works on a Rio 2016 Olympic medal at the Casa da Moeda do Brasil (Brazilian Mint) in Rio de Janeiro, Brazil, June 28, 2016. The Casa da Moeda do Brasil is the Brazilian mint, owned by the Brazilian government and administratively subordinated to the Ministry of Finances. It was established in 1694. (Photo by Sergio Moraes/Reuters)