python 虚拟环境

python3 目录venv创建为虚拟环境,并激活。

$ python3 -m venv ./venv
$ source venv/bin/activate

-m:   -m mod : run library module as a script (terminates option list)

$ python3 -m venv --help
usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear]
            [--upgrade] [--without-pip]
            ENV_DIR [ENV_DIR ...]

Creates virtual Python environments in one or more target directories.

positional arguments:
  ENV_DIR               A directory to create the environment in.

optional arguments:
  -h, --help            show this help message and exit
  --system-site-packages
                        Give the virtual environment access to the system
                        site-packages dir.
  --symlinks            Try to use symlinks rather than copies, when symlinks
                        are not the default for the platform.
  --copies              Try to use copies rather than symlinks, even when
                        symlinks are the default for the platform.
  --clear               Delete the contents of the environment directory if it
                        already exists, before environment creation.
  --upgrade             Upgrade the environment directory to use this version
                        of Python, assuming Python has been upgraded in-place.
  --without-pip         Skips installing or upgrading pip in the virtual
                        environment (pip is bootstrapped by default)

Once an environment has been created, you may wish to activate it, e.g. by
sourcing an activate script in its bin directory.

python2 创建虚拟目录

安装pip  , virtualenv 

wget https://bootstrap.pypa.io/get-pip.py --no-check-certificate
sudo python get-pip.py
sudo pip install virtualenv
virtualenv venv
source venv/bin/activate

 pip使用

https://docs.python.org/3/installing/