A ballet dancer practices in the sunshine at the Southbank skatepark in London on Monday, September 17, 2018, as Storm Helene is due to bring unseasonably warm weather in London and the south east, as the low pressure draws up warm air from the south. Forecasters have downgraded warnings that Helene could pose a risk to life when it hits this week – but warned coastal communities to stay vigilant. (Photo by Kirsty O'Connor/PA Wire)

A father crosses a road with his twin daughters in Shanghai, China September 28, 2018. (Photo by Aly Song/Reuters)

A girl stretches next to a pram on the embankment of the Moskva river in Moscow on October 18, 2018. The European part of Russia enjoys an unusually warm weather for the season with temperatures reaching up to 22 degrees centigrade. (Photo by Mladen Antonov/AFP Photo)

A boy holds a machine gun at a military hardware exhibition during a swear-in ceremony for new recruits of the Russian military-patriotic club “Yunarmia” (Young army) in the Black Sea port of Sevastopol, Crimea, October 27, 2018. (Photo by Pavel Rebrov/Reuters)

People assist a woman who was exposed to tear gas by pouring milk over her face after police fired tear gas and water canon to try and disperse protesters outside Parliament on November 17, 2020 in Bangkok, Thailand. The demonstrators gathered outside parliament, on Tuesday, as the Thai government met to discuss amendments to the country's constitution. (Photo by Lauren DeCicca/Getty Images)

Tigray refugees who fled the conflict in the Ethiopia's Tigray ride a bus going to the Village 8 temporary shelter, near the Sudan-Ethiopia border, in Hamdayet, eastern Sudan, Tuesday, December 1, 2020. (Photo by Nariman El-Mofty/AP Photo)

Students of Yuba Pratibha School, wearing a face shield and masks at school during a coronavirus pandemic in Kathmandu, Nepal, 26 November 2020. The head Teacher of Yuba Pratibha School, Yanga Raj Dahal, started to conduct classes for students, who can’t afford and attend online classes, with strict sanitary regime, providing also free face masks and shields for students. However majority of schools have been conducting online classes in Nepal from 19 March 2020 as part of precautionary measures against the spread of the coronavirus Covid-19. (Photo by Narendra Shrestha/EPA/EFE)

Mahmoud El Komy, a 26-year-old Egyptian mechatronics engineer, stands beside Cira 3, a remote-controlled robot that runs tests on suspected coronavirus disease (COVID-19) patients, to limit the human exposure to the virus, amid a second wave of infections in Tanta, Egypt, November 18, 2020. (Photo by Mohamed Abd El Ghany/Reuters)