Photo taken on Dec. 5, 2019 shows a terracotta warrior displayed at Emperor Qinshihuang's Mausoleum Site Museum in Xi'an, northwest China's Shaanxi Province. (Photos: Xinhua)

Photo taken on Dec. 5, 2019 shows a terracotta warrior displayed at Emperor Qinshihuang's Mausoleum Site Museum in Xi'an, northwest China's Shaanxi Province.

Photo taken on Dec. 5, 2019 shows a terracotta warrior displayed at Emperor Qinshihuang's Mausoleum Site Museum in Xi'an, northwest China's Shaanxi Province.

Photo taken on Dec. 5, 2019 shows a terracotta warrior displayed at Emperor Qinshihuang's Mausoleum Site Museum in Xi'an, northwest China's Shaanxi Province.

Photo taken on Dec. 5, 2019 shows a terracotta warrior displayed at Emperor Qinshihuang's Mausoleum Site Museum in Xi'an, northwest China's Shaanxi Province.