ImportError:需要“packaging.requirements”包

Question

我使用ubuntu运行VPS：

Distributor ID: Ubuntu
Description:    Ubuntu 14.04.5 LTS
Release:        14.04
Codename:       trusty

我试图将Python从2.7.6升级到2.7.16。

就在升级后，Gunicorn库没有从

Traceback (most recent call last):
  File "/home/user/bin/python-2.7/bin/gunicorn", line 7, in <module>
    from gunicorn.app.wsgiapp import run
  File "/home/user/bin/python-2.7/lib/python2.7/site-packages/gunicorn/app/wsgiapp.py", line 9, in <module>
    from gunicorn.app.base import Application
  File "/home/user/bin/python-2.7/lib/python2.7/site-packages/gunicorn/app/base.py", line 12, in <module>
    from gunicorn import util
  File "/home/user/bin/python-2.7/lib/python2.7/site-packages/gunicorn/util.py", line 12, in <module>
    import pkg_resources
  File "/home/user/bin/python-2.7/lib/python2.7/site-packages/pkg_resources/__init__.py", line 82, in <module>
    __import__('pkg_resources.extern.packaging.requirements')
  File "/home/user/bin/python-2.7/lib/python2.7/site-packages/pkg_resources/extern/__init__.py", line 61, in load_module
    "distribution.".format(**locals())
ImportError: The 'packaging.requirements' package is required; normally this is bundled with this package so if you get this warning, consult the packager of your distribution.

我被告知这可能是一些setuptools的问题，所以我用

python -m ensurepip
Looking in links: /tmp/tmp98U8zf
Requirement already satisfied: setuptools in ./bin/python-2.7/lib/python2.7/site-packages (41.1.0)
Requirement already satisfied: pip in ./bin/python-2.7/lib/python2.7/site-packages (19.2.2)

(无变动)

我试着做

pip install packaging

(无变动)

或将setuptools降级至19.2 (如Python2.7‘package’包是必需的；通常这与这个包捆绑在一起中所建议)

并得到了

  File "/home/user/bin/python-2.7/lib/python2.7/site-packages/gunicorn/config.py", line 8, in <module>
    import copy
  File "/home/user/bin/python-2.7/lib/python2.7/copy.py", line 52, in <module>
    import weakref
  File "/home/user/bin/python-2.7/lib/python2.7/weakref.py", line 14, in <module>
    from _weakref import (
ImportError: cannot import name _remove_dead_weakref

在我的例子中，有什么工作方法可以升级到2.7.16 python吗？

UPD：

我用它升级了python

wget https://www.python.org/ftp/python/2.7.16/Python-2.7.16.tgz
make clean && ./configure --enable-unicode=ucs4 --enable-shared --prefix=/home/user/bin/python-2.7/ --with-ensurepip=install && make && make install
pip install -r ~/django/django_projects/requirements.txt

pip冻结：https://www.pastiebin.com/5d592ea701503

谢谢。

Answer 1

场景

First:在尝试执行脚本时，将出现以下错误消息：

ImportError: The 'packaging.requirements' package is required; normally this is bundled with this package so if you get this warning, consult the packager of your distribution.

第二步:当尝试使用pip show setuptools检查setuptools版本时(或使用任何其他pip命令)，将出现下一个错误消息：

ImportError: cannot import name _remove_dead_weakref

原因

这是因为当前的Python安装在某种程度上搞砸了。在我的例子中，混乱是由从Ubuntu 16.04升级到Ubuntu 18.04造成的。

解决方案

虚拟环境

在最好的情况下，您已经在使用虚拟环境(这就是我的情况)。这里的解决方案是重新创建/重新设置您的venv (分步)：

$ cd /path/to/your/venv

# remove your old venv
$ rm -rf ./*

# create a new one
$ /usr/bin/virtualenv . --python=YOUR-PYTHON-VERSION

# activate venv
$ source bin/activate

# verify the correct python version is installed
$ python --version

例如，将YOUR-PYTHON-VERSION替换为python2.7或python3.7。

在重新创建你的静脉后，问题应该是解决的，你应该能够再次使用pip。

无虚拟环境

我认为解决这个问题的最好方法是完全卸载所有非默认的Python版本(例如，Ubuntu 18.04附带了Python 3.6+)，然后对所有其他所需的Python版本进行彻底的重新安装。

Answer 2

尝试通过键入以下内容来升级pip：

pip install --upgrade pip