mac brew install specific python version

 

1. Install the required version:

    % brew install python@3.7
    % brew list | grep python
    % brew ls python@3.7
    % ls -l /usr/local/Cellar/python@3.7/3.7.8_1/bin/python3.7
   

2. Add a soft link to /usr/local/bin/:

    % ln -s /usr/local/Cellar/python@3.7/3.7.8_1/bin/python3.7 /usr/local/bin/python3.7
    % python3.7 -V
   

3. Create a Python virtual environment:

    % python3.7 -m venv venv37
   

4. Enter the virtual environment:

    % source venv37/bin/activate
   

5. Exit the virtual environment:

    % deactivate

使用 virtualenv 建立 python 虛擬環境

安裝

pip install virtualenv

建立名為 venv 虛擬環境

virtualenv --python=/opt/python-3.6/bin/python venv

不指定路徑，直接使用版本

virtualenv venv --python=python2.7
virtualenv venv --python=python3.5
virtualenv venv --python=python3.6

若成功目錄底下會出現對應資料夾

使用虛擬環境

Linux / macOS

$ source ./venv/bin/activate

Windows

.\venv\Scripts\activate.bat

離開

deactivate 

from: https://blog.intemotech.com/%E4%BD%BF%E7%94%A8-virtualenv-%E5%BB%BA%E7%AB%8B-python-%E8%99%9B%E6%93%AC%E7%92%B0%E5%A2%83/