使用xlrd.book.book.sheet_by_name（）时，将“book”替换为笔记本变量名，出现一个属性错误，指出模块“xlrd.book”没有属性“book”。我已经检查过book对象是用xlrd而不是xlwt创建的。

def read_ws(wb, worksheet_name): 
    '''
    Opens a read_only copy of the worksheet.
    '''
    return xlrd.book.wb.sheet_by_name(worksheet_name)

def existing_start_sheet(path, ws_name, data):
    '''
    Reads and modifies and existing starter sheet.
    '''
    workbook = xlwt.Workbook(path)
    workbook_r = xlrd.open_workbook(path)
    r_ws = read_ws(workbook_r, ws_name)
    mod_start_sheet(workbook, r_ws, data)
    return

以下是我提到的文档：https://xlrd.readthedocs.io/en/latest/api.html?highlight=sheet_by_name#xlrd.book.book.sheet_by_name