python 实现在Excel末尾增加新行

import osimport xlrdimport xlwtfrom xlutils.copy import copydef excelwrite(L=None):	if L is None:		L = []	print(L)	filename = r'wldata.xls'	workbook = xlrd.open_workbook(filename, formatting_info=True)	sheet = workbook.sheet_by_index(0)	rowNum = sheet.nrows	colNum = sheet.ncols	newbook = copy(workbook)	newsheet = newbook.get_sheet(0)	# 在末尾增加新行	str = 'hehe'	newsheet.write(rowNum, 0, str)	# 覆盖保存	newbook.save(filename)