# pip python套件管理/env
### pip套件更新:

pip install --upgrade pip
pip3 install --upgrade pip3
python -m pip install 
pip install -U <packages>==<version>

### pip初始化
如果執行pip失敗，將pip初始化

python -m ensurepip --default-pip

### pip已安裝套件

pip list

### pip cache clean

pip cache remove *

### 導出環境安裝套件:

pip freeze > requirements.txt

### 由requirements文件安裝套件:

pip install -r requirements.txt

### special condition
:::warning
:warning:但在conda環境中使用`pip freeze > requirements.txt`，部分套件會顯示`@ file:///`而非實際版本，需要修改為
:::

pip list --format=freeze > requirements.txt

[Reference](https://blog.csdn.net/qq_36078992/article/details/109435000)
### proxy setting

pip config set global.proxy http://[username]:[password]@[proxy_server]:[port]