People walk in the Old Town during the first snowfall in Warsaw, Poland on Dec. 10, 2020. The first snow of this year fell upon Warsaw Thursday. (Photo by Jaap Arriens/Xinhua)

People walk in the Old Town during the first snowfall in Warsaw, Poland on Dec. 10, 2020. The first snow of this year fell upon Warsaw Thursday. (Photo by Jaap Arriens/Xinhua)

A woman takes a photo with mobile phone of Christmas decorations in the Old Town in Warsaw, Poland on Dec. 10, 2020. The first snow of this year fell upon Warsaw Thursday. (Photo by Jaap Arriens/Xinhua)

People walk in the Old Town during the first snowfall in Warsaw, Poland on Dec. 10, 2020. The first snow of this year fell upon Warsaw Thursday. (Photo by Jaap Arriens/Xinhua)