import pandas as pd # 从 CSV 文件中读取数据并设置索引 df = pd.read_csv("Nowcoder.csv",dtype=object) # 替换 Last_submission_time 列中的前两个斜杠 df["Last_submission_time"] = df["Last_submission_time"].str.replace("/","-",n=2) print(df[["Nowcoder_ID", "Le...