ValueError：没有名为对象类型<class'pandas.core.frame.DataFrame'的数据轴-Pandas

Question

我执行了下面的代码，并返回了错误。谁能帮我解决这个错误？非常感谢！！我需要阅读一个.xlsx文件，并对其他列分组的“ Valor”列求和，然后导出为.txt。文件。

.xlsx文件的数据：

enter image description here

错误：

Traceback (most recent call last):
  File "import.py", line 37, in <module>
    main()
  File "import.py", line 31, in main
    data_grouped = data.groupby('registro', 'Data')['Valor'].sum()
  File "C:\Users\morei\AppData\Local\Programs\Python\Python37\lib\site-packages\pandas\core\generic.py", line 7883, in groupby
    axis = self._get_axis_number(axis)
  File "C:\Users\morei\AppData\Local\Programs\Python\Python37\lib\site-packages\pandas\core\generic.py", line 411, in _get_axis_number
    raise ValueError("No axis named {0} for object type {1}".format(axis, cls))
ValueError: No axis named Data for object type <class 'pandas.core.frame.DataFrame'>

代码：

import os
import csv
import pandas as pd

def data_read(excel_data, sheet):
    df = pd.read_excel (excel_data, sheet)
    df.columns = df.columns.str.strip()
    return df

file_ = r'C:\Users\morei\Downloads\Morris\VENDAS KRUPP - Copia.xlsx' # raw string (r'string')

def main():
    for index_sheet in range (0, 1):
        data = data_read(file_, index_sheet)
        print (data)

        #types = data.dtypes
        #print (types)
        #new_types = data.astype({'registro': 'object', 'Data': 'object', 'Data.1': 'object', 'rubrica': 'object', 'em Branco': 'object'}).dtypes
        #print (new_types)

        #data_grouped = data.groupby([0, 2])[8].sum() # the numbers are columns indexes of ther sheet
        data_grouped = data.groupby('registro', 'Data')['Valor'].sum()

        print(data_grouped)
    print('Executed!')

if __name__ == "__main__":
    main()