一、Python安裝

1.下載安裝包

1 https://www.python.org/ftp/python/2.7.14/python-2.7.14.amd64.msi    # 2.7安裝包
2  
3 https://www.python.org/ftp/python/3.6.4/python-3.6.4-amd64.exe      # 3.6安裝包

2.安裝Python3.6

3.在命令行下測試

4. 安裝python2.7

5. 將python2增加到環境變量裏

1 C:\Python27\Scripts\;C:\Python27\;

6. 將C:\Python27目錄下的python.exe 和pythonw.exe 改為python2.exe 和pythonw2.exe

7. 將C:\Python36目錄下的python.exe 和pythonw.exe 改為python3.exe 和pythonw3.exe

8. 此時在命令行輸入python3代表python3 輸入python2代表python2

二、pip的安裝

1 #在cmd上執行 
2 python3 -m pip install --upgrade pip --force-reinstall
3 python2 -m pip install --upgrade pip --force-reinstall
4  
5  
6 #查看pip版本
7  
8 pip3 -V
9 pip2 -V

windows下安裝Python2和Python3共存