import pandas as pd
df1 = pd.read_csv('class_and_score.csv', encoding='gbk')
df2 = pd.read_csv('hight.csv', encoding='gbk')
df3 = pd.read_csv('width.csv', encoding='gbk')
#outfile = pd.merge(df1, df2,how='outer')
outfile = pd.concat([df1, df2, df3], axis=1)
outfile.to_csv('outfile.csv', index=False, encoding='gbk')
原来ABC三列分别在不同CSV文件里,结果如下: