用 pip 指令安裝套件時出現 WARNING: Ignoring invalid distribution 問題

今天在升版 pip 時出現 "WARNING: Ignoring invalid distribution" 訊息 :

D:\>pip install --upgrade pip    

WARNING: Ignoring invalid distribution -illow (c:\python37\lib\site-packages)

WARNING: Ignoring invalid distribution -illow (c:\python37\lib\site-packages)

Requirement already satisfied: pip in c:\python37\lib\site-packages (21.1.2)

WARNING: Ignoring invalid distribution -illow (c:\python37\lib\site-packages)

WARNING: Ignoring invalid distribution -illow (c:\python37\lib\site-packages)

WARNING: Ignoring invalid distribution -illow (c:\python37\lib\site-packages)

以前都不曾看過這種警語, 搜尋找到下面這篇 

# pip list 报错WARNING: Ignoring invalid distribution

原來要到括弧所示目錄下找到前面那個目錄, 將其刪除即可. 估計是上回安裝 Pillow 套件失敗留下的垃圾 : 

D:\>cd c:\python37\lib\site-packages 

用 dir 檢視此目錄, 果然找到 -illow 開頭的子目錄 :

用 del 指令刪除 ~illow-5.4.1.dist-info 子目錄後就不會出現警語了 :

c:\Python37\Lib\site-packages>del ~illow-5.4.1.dist-info   

c:\Python37\Lib\site-packages\~illow-5.4.1.dist-info\*，您確定要執行嗎 (Y/N)? y