ImportError:安装Pusher后无法导入名称certificate_transparency

Question

我用virtualenv env创建了一个virtualenv，然后(在采购env/bin/activate之后)用pip安装了pusher。但是，每当我试图运行我的模块时，我都会得到以下错误：

Traceback (most recent call last):
  File "/home/proc-daemon/google_appengine/google/appengine/runtime/wsgi.py", line 240, in Handle
    handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
  File "/home/proc-daemon/google_appengine/google/appengine/runtime/wsgi.py", line 299, in _LoadHandler
    handler, path, err = LoadObject(self._handler)
  File "/home/proc-daemon/google_appengine/google/appengine/runtime/wsgi.py", line 85, in LoadObject
    obj = __import__(path[0])
  File "/home/proc-daemon/supachat/supachat.py", line 31, in <module>
    ssl=True
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/pusher/pusher.py", line 52, in __init__
    json_encoder, json_decoder, backend, **backend_options)
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/pusher/pusher_client.py", line 34, in __init__
    json_encoder, json_decoder, backend, **backend_options)
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/pusher/client.py", line 20, in __init__
    from .requests import RequestsBackend
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/pusher/requests.py", line 17, in <module>
    import urllib3.contrib.pyopenssl
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/urllib3/contrib/pyopenssl.py", line 46, in <module>
    import OpenSSL.SSL
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/OpenSSL/__init__.py", line 8, in <module>
    from OpenSSL import crypto, SSL
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/OpenSSL/crypto.py", line 12, in <module>
    from cryptography import x509
  File "/home/proc-daemon/supachat/env/lib/python2.7/site-packages/cryptography/x509/__init__.py", line 7, in <module>
    from cryptography.x509 import certificate_transparency
ImportError: cannot import name certificate_transparency

所有的依赖项都正确安装，ls env/lib/python2.7/site-packages/cryptography/x509 显示(以及其他) certificate_transparency.pyc (和.py)。

是否有一种我没有意识到的安装pusher的不同方式？

Answer 1

所以，这不能解释这个问题，但它解决了这个问题。

我用错了后端。导入pusher.gae并设置backend=pusher.gae.GAEBackend解决了这个问题。