一、Centos中安装pip3和pip并存

一、python2
1.安装源

yum -y install epel-release

2.安装pip

yum install python-pip

3.对安装好的pip进行升级

pip install --upgrade pip （注意是两个短横线~~）

到这里pip 安装完成，即/usr/bin 目录下有pip , 但注意是python2 下的。

二、python3中pip3的安装
python3 中自带有pip3，因此只需要添加pip3的软链接即可

1.在之前装的python3 的/usr/bin 目录下有pip3 （创建软链接）

ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3

此时pip 和pip3 均可用~~

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本文出自：https://blog.csdn.net/gwz_6903/article/details/100678333

二、Centos中升级pip版本

出现“创建失败”这个问题一般是虚拟环境的问题，首先我们进入SSH（服务器命令行），手动安装一下virtualenv

升级pip

#pip3 -V
pip 9.0.3 from /usr/lib/python3.6/site-packages (python 3.6)

现在pip版本是9.0.3，安装插件会有警告，先升级pip

#pip3 install --upgrade pip
WARNING: Running pip install with root privileges is generally not a good idea. Try `pip3 install --user` instead.
Collecting pip
Downloading http://mirrors.cloud.aliyuncs.com/pypi/packages/43/84/23ed6a1796480a6f1a2d38f2802901d078266bda38388954d01d3f2e821d/pip-20.1.1-py2.py3-none-any.whl (1.5MB)
100% |████████████████████████████████| 1.5MB 95.6MB/s
Installing collected packages: pip
Successfully installed pip-20.1.1

查看下最新的pip版本

#pip -V
pip 20.1.1 from /usr/local/lib/python3.6/site-packages/pip (python 3.6)

pip升级完毕，下面安装virtualenv

#pip install virtualenv
Looking in indexes: http://mirrors.cloud.aliyuncs.com/pypi/simple/
Collecting virtualenv
Downloading http://mirrors.cloud.aliyuncs.com/pypi/packages/57/6e/a13442adf18bada682f88f55638cd43cc7a39c3e00fdcf898ca4ceaeb682/virtualenv-20.0.21-py2.py3-none-any.whl (4.7 MB)
|████████████████████████████████| 4.7 MB 13.3 MB/s
Collecting appdirs<2,>=1.4.3
Downloading http://mirrors.cloud.aliyuncs.com/pypi/packages/3b/00/2344469e2084fb287c2e0b57b72910309874c3245463acd6cf5e3db69324/appdirs-1.4.4-py2.py3-none-any.whl (9.6 kB)
Requirement already satisfied: six<2,>=1.9.0 in /usr/local/lib/python3.6/site-packages (from virtualenv) (1.14.0)
Collecting importlib-resources<2,>=1.0; python_version < "3.7"
Downloading http://mirrors.cloud.aliyuncs.com/pypi/packages/7f/2d/88f166bcaadc09d9fdbf1c336ad118e01b7fe1155e15675e125be2ff1899/importlib_resources-1.5.0-py2.py3-none-any.whl (21 kB)
Collecting filelock<4,>=3.0.0
Downloading http://mirrors.cloud.aliyuncs.com/pypi/packages/93/83/71a2ee6158bb9f39a90c0dea1637f81d5eef866e188e1971a1b1ab01a35a/filelock-3.0.12-py3-none-any.whl (7.6 kB)
Collecting distlib<1,>=0.3.0
Downloading http://mirrors.cloud.aliyuncs.com/pypi/packages/7d/29/694a3a4d7c0e1aef76092e9167fbe372e0f7da055f5dcf4e1313ec21d96a/distlib-0.3.0.zip (571 kB)
|████████████████████████████████| 571 kB 120.4 MB/s
Requirement already satisfied: importlib-metadata<2,>=0.12; python_version < "3.8" in /usr/local/lib/python3.6/site-packages (from virtualenv) (1.6.0)
Requirement already satisfied: zipp>=0.4; python_version < "3.8" in /usr/local/lib/python3.6/site-packages (from importlib-resources<2,>=1.0; python_version < "3.7"->virtualenv) (3.1.0)
Using legacy setup.py install for distlib, since package 'wheel' is not installed.
Installing collected packages: appdirs, importlib-resources, filelock, distlib, virtualenv
Running setup.py install for distlib ... done
Successfully installed appdirs-1.4.4 distlib-0.3.0 filelock-3.0.12 importlib-resources-1.5.0 virtualenv-20.0.21

查看一下virtualenv版本

#virtualenv --version
virtualenv 20.0.21 from /usr/local/lib/python3.6/site-packages/virtualenv/__init__.py

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本文出自：https://blog.csdn.net/ke2100/article/details/106443838/

三、创建虚拟环境

cd 进入项目所在根目录后，执行以下命令创建虚拟环境

python -m venv netease-cloud_venv

好了，现在再重新去python项目管理器创建项目试试，是不是不会出现“创建失败”了

本文出自：https://docs.python.org/3/tutorial/venv.html