Fighters of the pro-government Popular Resistance Committees militia carry a cannon as they transport it in parts to Yemen's southwestern war-torn city of Taiz December 26, 2015. (Photo by Reuters/Stringer)

A model presents creations by designer Filipe Faisca as part of his Spring/Summer 2017 collection show during Lisbon Fashion Week, Portugal, October 9, 2016. (Photo by Rafael Marchante/Reuters)

A man with a mask poses for a portrait as he takes part in festivities in honour of patron saint San Jeronimo in Masaya city, Nicaragua November 20, 2016. (Photo by Oswaldo Rivas/Reuters)

Revellers take part in the 21st Rio LGBT pride parade at Copacabana beach in Rio de Janeiro, Brazil, on December 11, 2016. (Photo by Yasuyoshi Chiba/AFP Photo)

A biplane taking part in the Vintage Air Rally lands, in Stellenbosch, near Cape Town, South Africa December 16, 2016. (Photo by Mike Hutchings/Reuters)

Troops of the Interior Ministry take part in a parade during a ceremony marking the Iraqi Police Day at a police academy in Baghdad January 9, 2016. (Photo by Khalid al Mousily/Reuters)

Participants take part in the annual Great Spitalfields Pancake Race in aid of London's Air Ambulance in London, Britain February 9, 2016. (Photo by Stefan Wermuth/Reuters)

A jockey drives a buffalo in the annual water buffalo race, part of a week-long festival in homage to the animals and in celebration of the rice harvest in Chonburi, Thailand on April 1, 2016. (Photo by Vichaya Pop/Barcroft Media)