how do I make excel table valid in python program if openpyxl can not understand extension (source)?

Question

I need to copy the content from a table to another: And I already converted the Excel table from xls to xlsx but confused about why it raise the error and warning? is there any way to make it works with the openpyxl module?

import os, openpyxl, re

os.chdir('C:\\Users\\Administrator.PC-20170525VYEL\\Desktop')

wb = openpyxl.load_workbook('sampleTemplate - 副本.xlsx')
sheets = wb.get_sheet_by_name('A级')

wb2 = openpyxl.load_workbook('sampleTemplate.xlsx')
newsheet = wb2.get_sheet_by_name('名单导入模版')


print('...')
phoneNumRegex = re.compile(r'\d{11}')

for row in range(2, sheets.max_row + 1):
    kidname = sheets['E' + str(row)].value        
    contact = sheets['C' + str(row)].vaule
    if contact == None:
        contact = 'None'
    else:
        contact = sheets['C' + str(row)].vaule
    contactNum = sheets['D' + str(row)].value
    conN = phoneNumRegex.findall(contactNum)
    if len(conN) >= 2:
        con1 = conN[1]
        con2 = conN[2]
    else:
        con1 = 'None'
    remark = sheet['a' + str(row)].value + ': ' + sheet['g' +   str(row)].value

    print('sampleTemplate.xlsx...')

    newsheet['c' + str(row)] = kidname
    newsheet['f' + str(row)] = contact
    newsheet['h' + str(row)] = con1
    newsheet['k' + str(row)] = con2
    newsheet['l' + str(row)] = remark

wb2.save('newsampleTemplate.xlsx')

the output error:

Warning (from warnings module):
  File "C:\Users\Administrator.PC-  20170525VYEL\AppData\Local\Programs\Python\Python36-32\lib\site-  packages\openpyxl\reader\worksheet.py", line 310
    warn(msg)
UserWarning: Unknown extension is not supported and will be removed
...
Traceback (most recent call last):
  File "C:\Users\Administrator.PC-20170525VYEL\Desktop\Autolist.py", line   22, in <module>
    contact = sheets['C' + str(row)].vaule
AttributeError: 'Cell' object has no attribute 'vaule'