取excel欄位值採用下面2種。n為工作表sheet、中括號內為欄位座標例['B1']
n['B'+str(g)].value = 3.07
n.cell(row=2, column=g).value = 3.07
使用上方的語法，程式跑得很順，
採用下方的語法，一定會在w.save('p310b.xlsx') 此行出錯，
但是cell()理應是openpyxl的內部函數，為什麼會造成存款出錯？？？
註：cell()在別的程式是好好的。

報錯：
Traceback (most recent call last):
File "C:\Users\CathyMe\AppData\Local\Programs\Python\Python38\lib\site-package
s\openpyxl\utils\cell.py", line 110, in get_column_letter
return _STRING_COL_CACHE[idx]
KeyError: 23703
Traceback (most recent call last):
File "p310.py", line 39, in
w.save('p310b.xlsx') # p310b.xlsx
File "C:\Users\CathyMe\AppData\Local\Programs\Python\Python38\lib\site-package
s\openpyxl\workbook\workbook.py", line 407, in save
save_workbook(self, filename)
File "C:\Users\CathyMe\AppData\Local\Programs\Python\Python38\lib\site-package
s\openpyxl\writer\excel.py", line 293, in save_workbook
writer.save()下略。

完整程式碼如下

import openpyxl, sys, time

w = openpyxl.load_workbook('p310.xlsx')
s = w.sheetnames # ['Sheet']
n = w['Sheet']

print(n.max_row)    # 23758
print(n.max_column) # 4

m = 0

for k in list(n['A']):
    if k.value == 'Garlic':
        m+=1 
print(m) # 630

for g in range(2, n.max_row+1):
    if n['A'+str(g)].value == 'Garlic':
        #n['B'+str(g)].value = 3.07		# Garlic new cost 3.07
        n.cell(row=2, column=g).value = 3.07
        
    #if n['A'][g].value == 'Garlic':
        #n.cell(row=2, column=g).value = 3.07  	# Garlic new cost 3.07
        #print(n['B'+str(g)].value) # Garlic origin cost 1.19
        #sys.exit()

    if n['A'+str(g)].value == 'Celery':
        n['B'+str(g)].value = 1.19  # Celery new cost 1.19

w.save('p310b.xlsx') # p310b.xlsx

time.sleep(8) # 因為當機才加了這行，給ram緩衝時間，然而沒用
w = openpyxl.load_workbook('p310b.xlsx')
n = w['Sheet']

for g in range(1, n.max_row+1):
    if n['A'+str(g)].value == 'Garlic':
        print(n['B'+str(g)].value) # Garlic new cost 3.07
        sys.exit()