Party-goers partake in a festival better known as Holi One, during International Workers Day in Johannesburg, South Africa, 01 May 2015. The colour festival promotes togetherness as well as colourness in everday life. May Day is observed worldwide every year on 01 May. (Photo by Kevin Sutherland/EPA)

A gibbon drinks from a soft drink bottle, given by a tourist, at a zoo in Kunming, Yunnan province, June 18, 2015. (Photo by Wong Campion/Reuters)

Students exercise in body training at Bishan Vocational Education Center in Chongqing, southwest China, January 13, 2016. These students were trained to be stewardesses of the high-speed train. (Photo by Xie Jie/Xinhua)

The coendou porcupine couple 'Joppi' (L) and 'Fletcher' nibble at a vegetables in their enclosure at the zoo in Frankfurt am Main, Germany, 03 December 2015. Coendou porcupines are nocturnal rodents related to porcupines and guinea pigs and native to the rain forests of Central and South America as well as Trinidad. (Photo by Arne Dedert/EPA)

A moon appears behind a windmill a day before the supermoon is full on September 8, 2014 in Consuegra, in Toledo province, Spain. Consuegra belongs to a region made famous by the novel “Don Quijote de la Mancha” (Don Quixote) writed by Miguel De Cervantes. Some of the windmills belong to the 16th century. (Photo by Pablo Blazquez Dominguez/Getty Images)

Youths parade wearing World War Two uniforms during the Independence Day celebrations in Gdansk November 11, 2014. (Photo by Lukasz Glowala/Reuters/Agencja Gazeta)

A Sphynx cat stares sitting on its owner's lap during an international feline beauty competition in Bucharest, Romania, Saturday, April 14, 2018. More than 250 cats take part in the two-day competition in the Romanian capital. (Photo by Vadim Ghirda/AP Photo)

A woman with high heels walks on a sidewalk which is renovated on August 10, 2017 in downtown Moscow, as the city continues with preparations for next year's FIFA World Cup. (Photo by Mladen Antonov/AFP Photo)