导入错误：无法导入名称“证书”

Question

我在过去 2 天遇到此错误。python requests 库似乎有问题，但我已经重新安装了几次，但没有成功。

Traceback (most recent call last):
    File "project-src/bla-blah/manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
    File "project-src\env\lib\site-packages\django\core\management\__init__.py", line 385, in execute_from_command_line
    utility.execute()
    File "project-src\env\lib\site-packages\django\core\management\__init__.py", line 354, in execute
    django.setup()
    File "project-src\env\lib\site-packages\django\__init__.py", line 21, in setup
    apps.populate(settings.INSTALLED_APPS)
    File "project-src\env\lib\site-packages\django\apps\registry.py", line 85, in populate
    app_config = AppConfig.create(entry)
    File "project-src\env\lib\site-packages\django\apps\config.py", line 112, in create
    mod = import_module(mod_path)
    File "C:\Python34\lib\importlib\__init__.py", line 109, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
    File "<frozen importlib._bootstrap>", line 2254, in _gcd_import
    File "<frozen importlib._bootstrap>", line 2237, in _find_and_load
    File "<frozen importlib._bootstrap>", line 2226, in _find_and_load_unlocked
    File "<frozen importlib._bootstrap>", line 1200, in _load_unlocked
    File "<frozen importlib._bootstrap>", line 1129, in _exec
    File "<frozen importlib._bootstrap>", line 1471, in exec_module
    File "<frozen importlib._bootstrap>", line 321, in _call_with_frames_removed
    File "project-src\env\lib\site-packages\social\apps\django_app\__init__.py", line 14, in <module>
    from social.apps.django_app.utils import load_strategy
    File "project-src\env\lib\site-packages\social\apps\django_app\utils.py", line 12, in <module>
    from social.backends.utils import get_backend
    File "project-src\env\lib\site-packages\social\backends\utils.py", line 2, in <module>
    from social.backends.base import BaseAuth
    File "project-src\env\lib\site-packages\social\backends\base.py", line 1, in <module>
    from requests import request, ConnectionError
    File "project-src\env\lib\site-packages\requests\__init__.py", line 58, in <module>
    from . import utils
    File "project-src\env\lib\site-packages\requests\utils.py", line 24, in <module>
    from . import certs

    ImportError: cannot import name 'certs'

也许是 2 天前 Windows 7 更新的问题，因为这是最近几天唯一发生变化的地方。

顺便说一下，我使用的是带有 virtualenv、PyCharm 3.4.1 IDE 和 Win7 的 python 3.4。

在certs.py 中有问题的代码（最后一行）：

try:
    from certifi import where
except ImportError:
    def where():
        """Return the preferred certificate bundle."""
        # vendored bundle inside Requests
        return os.path.join(os.path.dirname(__file__), 'cacert.pem')

Answer 1

这对我有用（重新安装请求库）：

pip uninstall requests pip install requests

Answer 2

如果你想知道这个问题发生了什么......我重新安装了操作系统，再次下载了 git 项目，重新配置了 python virtualenv 并且“神奇地”它工作了。所以我确信某处存在配置错误，但这不是请求库问题。

如果您遇到同样的问题，我鼓励您安装一个全新的环境。