在 Pandas中，drop_duplicates() 提供了删除重复值的功能，这个方法主要帮助我们删除后出现的重复值。例如，某列数据如下：Open： Open1 12 23 删除后变为 34 43 那么以下哪种参数可以帮助我们实现删除先出现的重复值。

Pandas中的数据结构中表示数据框的是（） -Who knows what pandas and sheep like eating? -I know pandas like eating_______ and sheep like eating grass. Pandas will have enough places. Do you ever play ___ pandas?[ ] Giant pandas are on the verge of extinction. pandas中head（n）的意思是获取最后的n行数据（） ______he like pandas?–Because they are interesting. This kind of bamboo is suitable _____ pandas _____ eat.[ ] Let's go to the ________ to see the pandas. Why do you want to see the pandas? -Because they are . This kind of bamboo is not suitable_____pandas _____ eat.[ ] ____ does he like pandas?—Because they are cute. Why do you like pandas? ——Because they are very___ Mother giant pandas have only one or two babies . [ ] ________ giant pandas is getting _________ because their living areas are becoming farmlands There aren’t many pandas________in the world today. _____ of giant pandas is getting ______ because their living areas are becoming farmlands. ________ of giant pandas is getting _________ because their living areas are becoming farmland. Why ______Kate like pandas ? —-Because it’s very cute. When the baby pandas see the keepers, they run over with excitement.