A boy covers his head with fallen leaves as he enjoys a stroll with his family in a park in downtown Frankfurt, Germany, November 6, 2016. (Photo by Kai Pfaffenbach/Reuters)

A demonstrator wearing a mask is seen during a protest against the government's restrictions amid the coronavirus disease (COVID-19) outbreak, in Berlin, Germany, August 1, 2020. (Photo by Christian Mang/Reuters)

In this aerial image, debris of the Japanese Imperial Navy fighter A6M “Zero” is seen in the field on August 29, 2016 in Babeldaob Island, Palau. The war was opened up 75 years ago by Imperial Japan against the allied forces, including the United States, by the Pearl Harbour attack on December 7, 1941, claimed more than 2 million lives until Japan's surrender in 1945. (Photo by The Asahi Shimbun via Getty Images)

Common seals are reintroduced to the wild on the beach of the island Juist, Germany, 28 July 2014. It is the first reintroduction to the wild drive of the seal breading station Norddeich this year. (Photo by Carmen Jaspersen/EPA)

A handout TV grab made available by the Demiroren News Agency (DHA) on September 12, 2020, shows a freak sandstorm sweeping over Polatli, in Ankara, on September 12, 2020. A freak sandstorm hit Ankara on September 12, 2020, the Turkish capital's mayor said, as officials said six people were injured after strong winds. (Photo by Handout/DHA via AFP Photo)

Iranians wearing face masks against the Covid-19 coronavirus attends Laylat al-Qadr prayers, one of the holiest nights during the Muslim fasting month of Ramadan, outside a mosque in the Tehran, on May 13, 2020. (Photo by Atta Kenare/AFP Photo)

Former Olympic gymnast Nastia Liukin performs a flip while throwing the ceremonial first pitch during a baseball game between the Los Angeles Angels and the Tampa Bay Rays, Friday, July 14, 2017, in Anaheim, Calif. (Photo by Jae C. Hong/AP Photo)

In this photograph taken on February 18, 2016, Pakistani children ride on swings in the predominantly Pashtun Korangi District of Karachi. In a rundown district of Karachi, Rabia balks at a neighbour's proposal to vaccinate her children, demonstrating one of the biggest hurdles to eradicating polio in Pakistan by the end of the year: confused and frightened parents. (Photo by Asif Hassan/AFP Photo)