Anti-frost candles burn in apricot plantations to protect flowering buds and blossoms from frost in the midst of the Swiss Alps, in Saxon, Canton of Valais, Switzerland, 05 April 2019. With an unusually low temperature forecast for the season, fruit growers try to protect their buds from frost damage with two different means, icy water or large candles. (Photo by Valentin Flauraud/EPA/EFE)

Jaime “Ka Diego” Padilla (R), spokesperson of the Melito Glor Command of the New People's Army (NPA), and Ka Kathryn (Comrade Kathryn) (L) react during their 50th founding anniversary celebration at an undisclosed location in the mountains of Sierra Madre, Philippines, 31 March 2019. (Photo by Alecs Ongcal/EPA/EFE)

Robots serve trays with food to customers waiting at the Robot theme restaurant in Bangalore, India, 17 August 2019. Six robots are deployed as waiters at the the robot-themed Robot restaurant where each table is equipped with a tablet to place one's order. (Photo by Jagadeesh N.V./EPA/EFE)

A morning fog is seen in the Siberian city of Omsk, Russia on October 8, 2019. (Photo by Alexey Malgavko/Reuters)

Belgium's Crown Princess Elisabeth poses with dancers and youth after a ceremony on the occasion of her 18th birthday, outside the Royal Palace in Brussels, Belgium on October 25, 2019. (Photo by Yves Herman/Reuters)

This photo shows sunset in Eagle, Colo., Sunday, November 3, 2019. Daylight saving time ended, making sunset around 5 p.m. this time of year in Colorado. (Photo by Chris Dillmann/Vail Daily via AP Photo)

Labourers push wooden boards before carrying them to construct a temporary pontoon bridge over the Ganges river for the upcoming Hindu festival of Magh Mela in Allahabad on November 24, 2019. The Magh Mela is held every year on the banks of Triveni Sangam – the confluence of the three great rivers Ganga, Yamuna and the mystical Saraswati – in Allahabad during the Hindu month of Magh which corresponds to mid January – mid February. (Photo by Sanjay Kanojia/AFP Photo)

A partial solar eclipse is seen as a labourer works at a construction site in Phnom Penh, Cambodia, March 9, 2016. (Photo by Samrang Pring/Reuters)