ImportError：没有名为类型的模块

Question

I'm trying to create apython2 virtualenv , so I try pip install virtualenv and get

Traceback (most recent call last):
  File "/usr/local/bin/pip", line 11, in <module>
    load_entry_point('pip==21.1.1', 'console_scripts', 'pip')()
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 489, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 2843, in load_entry_point
    return ep.load()
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 2434, in load
    return self.resolve()
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 2440, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/Library/Python/2.7/site-packages/pip-21.1.1-py2.7.egg/pip/__init__.py", line 1, in <module>
    from typing import List, Optional
ImportError: No module named typing

I get an almost identical error with pip install typing

 Traceback (most recent call last): File "/usr/local/bin/pip", line 11, in <module> load_entry_point('pip==21.1.1', 'console_scripts', 'pip')() File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 489, in load_entry_point return get_distribution(dist).load_entry_point(group, name) File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 2843, in load_entry_point return ep.load() File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 2434, in load return self.resolve() File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources/__init__.py", line 2440, in resolve module = __import__(self.module_name, fromlist=['__name__'], level=0) File "/Library/Python/2.7/site-packages/pip-21.1.1-py2.7.egg/pip/__init__.py", line 1, in <module> from typing import List, Optional ImportError: No module named typing

A lot of solutions suggest using python3 but I'm specifically trying to create a python 2 virtual environment

---

I'm running MacOS Big Sur on a 2018 Intel i3 Mac Mini

Answer 1

Python 2 reached its end of life (EOL). Consequently the support for Python 2 was removed from pip in version 21. You need to downgrade pip to version 20.

---

I tried this (in shell command line):

# downgrade pip to 20.3.4
pip install --user pip==20.3.4
# better: 'pip<21', but it must be quoted!

# install virtualenv if not installed already
pip install --user virtualenv

# create a new venv for old python
virtualenv -p /usr/bin/python2.7 /tmp/venv27

# update pip back to the recent version
pip install --user --upgrade pip

Now, pip --version shows version 21, but inside the activated environment there is version 20:

sh-5.0$ pip --version
pip 21.1.1 from /home/vpfb/.local/lib/python3.9/site-packages/pip (python 3.9)

sh-5.0$ pwd
/tmp/venv27/bin

sh-5.0$ source ./activate

(venv27) sh-5.0$ pip --version
pip 20.3.4 from /tmp/venv27/lib/python2.7/site-packages/pip (python 2.7)

I tried to install a random package in the venv and it succeeded.

Answer 2

I'm afraid you'll have to use another version. I know you've been hearing this a lot, but python 2.7 isn't supported anymore (since 1st January 2021) so thats why it might be showing an error.

Answer 3

typing is

New in version 3.5.

So it should be no surprise that import typing caused failure in python2.7 . So if you find project using import typing is either for python at least 3.5 or is using typing different from built-in module. If you know to want ramifications of python2 end of life read Sunsetting Python 2 . If you have legacy python2 you might try porting to python3

Answer 4

pip stopped supporting Python 2 in version 21 . You'll need to install an older version of pip for Python 2.

Answer 5

typing module is only valid for python version 3.5 and above.

https://pypi.org/project/typing/