AttributeError: module 'pip._vendor.requests' has no attribute 'Session' when creating a virtual env

[Neraste]

Context

• Python version: 3.6.5;
• Pip version: 18.1 (same with 10);
• Operating system: Open SuSE Leap 15.

Descritption

Dear virtualenv dev team, on a fresh install of Python, when trying to create a virtual environment, I get an error and the creation is aborted.

What I did

Input:

virtualenv -p python3 env

Output:

Already using interpreter /usr/bin/python3
Using base prefix '/usr'
New python executable in /home/neraste/my_project/env/bin/python3
Not overwriting existing python script /home/neraste/my_project/env/bin/python (you must use /home/neraste/my_project/env/bin/python3)
Installing setuptools, pip, wheel...
  Complete output from command /home/neraste/my_project/env/bin/python3 - setuptools pip wheel:
  Traceback (most recent call last):
  File "<stdin>", line 9, in <module>
  File "/usr/lib64/python3.6/pkgutil.py", line 624, in get_data
    importlib._bootstrap._load(spec))
  File "<frozen importlib._bootstrap>", line 684, in _load
  File "<frozen importlib._bootstrap>", line 656, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 626, in _load_backward_compatible
  File "/usr/lib/python3.6/site-packages/virtualenv_support/pip-10.0.1-py2.py3-none-any.whl/pip/_vendor/requests/__init__.py", line 83, in <module>
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 656, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 626, in _load_backward_compatible
  File "/usr/lib/python3.6/site-packages/virtualenv_support/pip-10.0.1-py2.py3-none-any.whl/pip/_internal/__init__.py", line 42, in <module>
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 656, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 626, in _load_backward_compatible
  File "/usr/lib/python3.6/site-packages/virtualenv_support/pip-10.0.1-py2.py3-none-any.whl/pip/_internal/cmdoptions.py", line 16, in <module>
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 656, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 626, in _load_backward_compatible
  File "/usr/lib/python3.6/site-packages/virtualenv_support/pip-10.0.1-py2.py3-none-any.whl/pip/_internal/index.py", line 25, in <module>
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 656, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 626, in _load_backward_compatible
  File "/usr/lib/python3.6/site-packages/virtualenv_support/pip-10.0.1-py2.py3-none-any.whl/pip/_internal/download.py", line 326, in <module>
AttributeError: module 'pip._vendor.requests' has no attribute 'Session'
----------------------------------------
...Installing setuptools, pip, wheel...done.
Traceback (most recent call last):
  File "/usr/bin/virtualenv", line 11, in <module>
    load_entry_point('virtualenv==15.1.0', 'console_scripts', 'virtualenv')()
  File "/usr/lib/python3.6/site-packages/virtualenv.py", line 713, in main
    symlink=options.symlink)
  File "/usr/lib/python3.6/site-packages/virtualenv.py", line 945, in create_environment
    download=download,
  File "/usr/lib/python3.6/site-packages/virtualenv.py", line 901, in install_wheel
    call_subprocess(cmd, show_stdout=False, extra_env=env, stdin=SCRIPT)
  File "/usr/lib/python3.6/site-packages/virtualenv.py", line 797, in call_subprocess
    % (cmd_desc, proc.returncode))
OSError: Command /home/neraste/my_project/env/bin/python3 - setuptools pip wheel failed with error code 1

[asottile]

I think you're creating a virtualenv over an existing env, try rm -rf env && virtualenv -ppython3 env

[gaborbernat]

See as per above.