使用 Virtualenv

1. 安裝 virtualenv $ pip install virtualenv
2. virtualenv venv 在我們想要新增虛擬環境的專案資料夾下新增一個 venv ， venv 是我們取的一個名字，可隨自己喜好
3. source venv/bin/activate 啟動虛擬環境，就會發現 terminal 上多了一個 (venv) ，表示啟動成功。若是用 fish 的人會發現無法啟動，可以改打成 source venv/bin/activate.fish
4. 啟動成功後就可以像平常一樣下指令安裝。
5. 退出虛擬環境 deactivate

實際執行畫面

安裝 virtualenv
$ pip install virtualenv

新增 virtualenv 的專案
$ virtualenv flask_project
New python executable in /Users/rita/Desktop/flask_project/bin/python
Installing setuptools, pip, wheel...done.

啟動 virtualenv
$ source flask_project/bin/activate

成功啟動之後，進入該資料夾，clone Repository
(flask_project) $ cd flask_project/
(flask_project) $ git clone [email protected]:q0u04bj3/flask-skeleton.git
Cloning into 'flask-skeleton'...
remote: Counting objects: 354, done.
remote: Compressing objects: 100% (16/16), done.
remote: Total 354 (delta 4), reused 16 (delta 4), pack-reused 334
Receiving objects: 100% (354/354), 51.28 KiB | 0 bytes/s, done.
Resolving deltas: 100% (157/157), done.
Checking connectivity... done.

安裝程式庫
(flask_project) $ pip install Flask
Collecting Flask
  Downloading Flask-0.12.2-py2.py3-none-any.whl (83kB)
    100% |████████████████████████████████| 92kB 627kB/s
Collecting click>=2.0 (from Flask)
  Downloading click-6.7-py2.py3-none-any.whl (71kB)
    100% |████████████████████████████████| 71kB 2.6MB/s
Collecting itsdangerous>=0.21 (from Flask)
  Downloading itsdangerous-0.24.tar.gz (46kB)
    100% |████████████████████████████████| 51kB 5.1MB/s
Collecting Werkzeug>=0.7 (from Flask)
  Downloading Werkzeug-0.12.2-py2.py3-none-any.whl (312kB)
    100% |████████████████████████████████| 317kB 1.5MB/s
Collecting Jinja2>=2.4 (from Flask)
  Downloading Jinja2-2.9.6-py2.py3-none-any.whl (340kB)
    100% |████████████████████████████████| 348kB 278kB/s
Collecting MarkupSafe>=0.23 (from Jinja2>=2.4->Flask)
  Downloading MarkupSafe-1.0.tar.gz
Building wheels for collected packages: itsdangerous, MarkupSafe
  Running setup.py bdist_wheel for itsdangerous ... done
  Stored in directory: /Users/rita/Library/Caches/pip/wheels/fc/a8/66/24d655233c757e178d45dea2de22a04c6d92766abfb741129a
  Running setup.py bdist_wheel for MarkupSafe ... done
  Stored in directory: /Users/rita/Library/Caches/pip/wheels/88/a7/30/e39a54a87bcbe25308fa3ca64e8ddc75d9b3e5afa21ee32d57
Successfully built itsdangerous MarkupSafe
Installing collected packages: click, itsdangerous, Werkzeug, MarkupSafe, Jinja2, Flask
Successfully installed Flask-0.12.2 Jinja2-2.9.6 MarkupSafe-1.0 Werkzeug-0.12.2 click-6.7 itsdangerous-0.24
You are using pip version 8.1.0, however version 9.0.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

參考資料

Real Python Flask Starter Project