People gather on a hill near the Chopin Airport to watch aeroplanes taking off, in Warsaw, Poland, Sunday, September 9, 2018. (Photo by Alik Keplicz/AP Photo)

A girl shows a fish she has caught in a bare- hand fish catching contest held in Housangyuan Village of Lyutan Township Wuyi County, east China' s Zhejiang Province, September 23, 2018. People across China hold various activities to celebrate the country' s first Farmers' Harvest Festival, which falls on Sept. 23 this year. (Photo by Zhang Jiancheng/Xinhua News Agency/Barcroft Images)

A performer entertains the crowd during a rally in support of the leader of the Cameroonian opposition party Movement for the Rebirth of Cameroon (MRC) in Yaounde, on September 30, 2018, prior to the upcoming October 7, presidential elections. (Photo by Marco Longari/AFP Photo)

Yogis, Israeli and foreigners, participate in the Arava Yoga Annual festival at the ancient copper mines area of the Timna Valley, in the southern Arava region of Israel, north of Eilat on November 2, 2018. (Photo by Menahem Kahana/AFP Photo)

A young Sandinista guerrilla takes aim with his 45 pistol as he stands waiting to do combat with the Nicaraguan National Guard in Managua June 23, 1979. The guerrillas still occupy major parts of the Capitol City. (Photo by McLendon/AP Photo)

Children play in water to beat the heat during the Muslim holy month of Ramadan amid lockdown of the Sindh province due to the ongoing coronavirus COVID-19 disease pandemic in Karachi, Pakistan, 28 April 2020. Muslims around the world celebrate the holy month of Ramadan, by praying during the night time and abstaining from eating, drinking, and sexual acts during the period between sunrise and sunset. Ramadan is the ninth month in the Islamic calendar and it is believed that the revelation of the first verse in Koran was during its last 10 nights. (Photo by Shahzaib Akber/EPA/EFE)

A boy walks by a model of a dinosaur wearing a face mask, during a partial lockdown to prevent the spread of the coronavirus, at the Museum of Natural History in Brussels, Tuesday, May 19, 2020. Museums are hesitantly starting to reopen as the coronavirus lockdown measures are relaxed, yet experts say that one in eight in the world could potentially face permanent closure because of the pandemic. (Photo by Virginia Mayo/AP Photo)

A cafe-restaurant staff stands outside as people drink coffee in Monastiraki district of Athens, on Monday, May 25, 2020. Greece restarted regular ferry services to its islands Monday, and cafes and restaurants were also back open for business as the country accelerated efforts to salvage its tourism season. (Photo by Petros Giannakouris/AP Photo)