报错机器：
excel = pd.ExcelFile(load_workbook(file,read_only=False), engine="openpyxl")
sheet = excel.book[sheet_name]
df = excel.parse(sheet_name, header=header)
for item in sheet.merged_cells:
print(sheet.merged_cells.class)
#
print(item.class)
#
正常机器：
for item in sheet.merged_cells:
print(sheet.merged_cells.class)
#
print(item.class)
#
item 在错误机器上显示的父类
openpyxl, item, class__, print
