安装了virtualenv，但仍然出现“ ModuleNotFoundError：没有名为“ virtualenv”的模块”错误

Question

I'm using CentOS 7 and want to run a "virtualenv" command. So I tried uninstalling and re-installing it ...

[myuser@server ~]$ sudo pip uninstall virtualenv
DEPRECATION: Python 2.7 will reach the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 won't be maintained after that date. A future version of pip will drop support for Python 2.7.
Cannot uninstall 'virtualenv'. It is a distutils installed project and thus we cannot accurately determine which files belong to it which would lead to only a partial uninstall.
[myuser@server ~]$ sudo pip install virtualenv
DEPRECATION: Python 2.7 will reach the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 won't be maintained after that date. A future version of pip will drop support for Python 2.7.
Requirement already satisfied: virtualenv in /usr/lib/python2.7/site-packages (15.1.0)

but when I go to actually run it, I'm told its not installed.

[myuser@server ~]$ virtualenv myenv
Traceback (most recent call last):
  File "/usr/bin/virtualenv", line 2, in <module>
    import virtualenv
ModuleNotFoundError: No module named 'virtualenv'

WTF??

Answer 1

You can just remove virtualenv rm -r ./your_venv and after that create new one python3 -m virtualenv your_venv and activate this source ./your_venv/bin/activate . Now you are in separated environment. In this state you can install your libs pip install -r ./requirements.txt for example. The libs are going to install only inside your environment, not globally.

Answer 2

try python -m virtualenv myenv . The -m flag means module. With this command, you are explicitly telling python to run the module virtualenv as a script.