A remote-controlled plane in the form of a witch flies over a neighborhood as the sun sets during Halloween in Encinitas, California, U.S. October 31, 2016. (Photo by Mike Blake/Reuters)

Climbers place a huge 80x80 metres (262x262 feet) Swiss national flag on the western face of the north-eastern Swiss landmark Mount Saentis, Switzerland on July 31, 2018. (Photo by Arnd Wiegmann/Reuters)

Vishnu Limbachiya, a hair artist, styles the hair of a man while wearing a blindfold at a park in Ahmedabad, India, May 31, 2017. (Photo by Amit Dave/Reuters)

A worker roasts rows of freshly slaughtered pigs, known locally as “lechon” and famously served as main courses during the New Year revelry, at a store in Manila, Philippines, December 31, 2016. (Photo by Ezra Acayan/Reuters)

Women take a selfie next to a police officer as they take part in New Year's Eve celebrations in the Bund, in Shanghai, China December 31, 2016. (Photo by Aly Song/Reuters)

A young girl gives a banana to a tamed baboon on the outskirts of Beira, Mozambique, Sunday, March, 31, 2019. Cholera cases among cyclone survivors in Mozambique have jumped to 271, authorities said. So far no cholera deaths have been confirmed. (Photo by Tsvangirayi Mukwazhi/AP Photo)

A glass skywalk in Wanyuan, Sichuan province, built along the side of a cliff, is the highest such skywalk anywhere in China on January 31, 2017. Some visitors have been proven to be terrified by the experience had to brace against the wall in fear. (Photo by Chinanew.com/AsiaWire)

French twins Thomas and Vincent (L) Seris take the tram in Bordeaux, November 12, 2014. Born with Xeroderma Pigmentosum (XP), the twins cannot be exposed to the sun and its ultraviolet (UV) light, which could provoke precocious cancers due to an autosomal recessive genetic disorder of DNA repair. Colloquially referred to as Children of the Night (Les Enfants de la Lune) the Seris twins are among 70 to 80 people in France who suffer from the genetic defect. The French association “Les Enfants de la Lune” reports that there are between five and ten thousand such cases in the world. Thomas and Vincent have been testing a new protective mask for the last year which is transparent and ventilated and developed by several hospitals in France. (Photo by Regis Duvignau/Reuters)