pd 中的groupby函数

import pandas as pd
import  numpy as np


df = pd.DataFrame({'key1':list('aabba'),
                  'key2': ['one','two','one','two','one'],
                  'data1': ['1','3','5','7','9'],
                  'data2': ['2','4','6','8','10']})
print(df)


grp = list(df.groupby('key1'))

print(grp)

print(grp[0])

print(grp[0][0])

print(grp[0][1])