python-檔案讀取與寫入

以下代碼測試通過
#檔案的讀取與寫入
str1 = input('請輸入任意字元：')
list1 = []#存儲字條串
list2 = []#存儲整型資料
for i in str1:
    if i.isdigit():
        list2.append(int(i))
    else:
        list1.append(i.upper())
print(list1)
print(list2)
f = open(r'C:\Users\Administrator\Desktop\myfile.txt','a')
for i in list1:
    f.write(i)
f.close()