Virtualenv 一直由 python 2 而不是 python 3 构建

Question

在尝试为 python 创建虚拟环境时，我不断收到以下错误。在我看来，virtualenv/pip 默认使用 python 2，而不是在构建环境时。 不该环境是 为 python2 制作的，但它是 由制作的蟒蛇2。我认为这是问题所在，感谢任何帮助。

[brad@reason Attack_Analysis]$ virtualenv -p /usr/local/bin/python3.7 venv
Running virtualenv with interpreter /usr/local/bin/python3.7
Using base prefix '/usr/local'
New python executable in /home/brad/Development/Attack_Analysis/venv/bin/python3.7
Also creating executable in /home/brad/Development/Attack_Analysis/venv/bin/python
Installing setuptools, pip, wheel...

  Complete output from command /home/brad/Developme...s/venv/bin/python3.7 - setuptools pip wheel:
  Traceback (most recent call last):
  File "<stdin>", line 8, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/__init__.py", line 40, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/cli/autocompletion.py", line 8, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/cli/main_parser.py", line 12, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/commands/__init__.py", line 6, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/commands/completion.py", line 6, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/cli/base_command.py", line 18, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/download.py", line 38, in <module>
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/_internal/utils/glibc.py", line 3, in <module>
  File "/usr/local/lib/python3.7/ctypes/__init__.py", line 7, in <module>
    from _ctypes import Union, Structure, Array
ModuleNotFoundError: No module named '_ctypes'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 11, in <module>
ImportError: cannot import name 'main' from 'pip' (/home/brad/.local/lib/python2.7/site-packages/virtualenv_support/pip-18.1-py2.py3-none-any.whl/pip/__init__.py)
----------------------------------------
...Installing setuptools, pip, wheel...done.
Traceback (most recent call last):
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv.py", line 2438, in <module>
    main()
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv.py", line 768, in main
    symlink=options.symlink,
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv.py", line 1030, in create_environment
    install_wheel(to_install, py_executable, search_dirs, download=download)
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv.py", line 983, in install_wheel
    call_subprocess(cmd, show_stdout=False, extra_env=env, stdin=script)
  File "/home/brad/.local/lib/python2.7/site-packages/virtualenv.py", line 861, in call_subprocess
    raise OSError("Command {} failed with error code {}".format(cmd_desc, proc.returncode))
OSError: Command /home/brad/Developme...s/venv/bin/python3.7 - setuptools pip wheel failed with error code 1

我的 vitualenv 是最新的

[brad@reason Attack_Analysis]$ virtualenv --version
16.2.0

我的 pip 已更新，但它似乎适用于 python 2，而不是 3。如何让它适用于 python 3？我在 redhat 7.5 上通过 make install 安装。

[brad@reason Attack_Analysis]$ pip --version
pip 18.1 from /usr/lib/python2.7/site-packages/pip (python 2.7)

在使用pip3的时候，好像发现没有root，但是没有root，所以我的pip3已经过时了。当我需要 root 来执行此操作并遇到此问题时，不确定如何更新它。

[brad@reason ~]$ pip3 --version
pip 9.0.3 from /usr/local/lib/python3.6/site-packages (python 3.6)
[brad@reason ~]$ sudo pip3 install --upgrade pip
[sudo] password for brad: 
sudo: pip3: command not found

我的 PYTHONPATH 是空的。应该是吗？我不认为我以前更改过这个，不确定这是否是一个问题。

[brad@reason ~]$ echo $PYTHONPATH

[brad@reason ~]$

Answer 1

这就是我解决这个问题的方法（在 Linux 上）：

apt install python3-pip
pip3 install virtualenv