安装几乎所有库的pip问题

Question

我很难使用pip来安装几乎任何东西。我对编码不熟悉，所以我想也许这是我一直在做的错误的事情，我选择了easy_install来完成我需要做的大部分事情，这通常是有效的。然而，现在我试图下载nltk库，也没有完成这项工作。

我试图进入

sudo pip install nltk

但得到了如下回应：

/Library/Frameworks/Python.framework/Versions/2.7/bin/pip run on Sat May  4 00:15:38 2013
Downloading/unpacking nltk

  Getting page https://pypi.python.org/simple/nltk/
  Could not fetch URL [need more reputation to post link]: There was a problem confirming the ssl certificate: <urlopen error [Errno 1] _ssl.c:504: error:0D0890A1:asn1 encoding routines:ASN1_verify:unknown message digest algorithm>

  Will skip URL [need more reputation to post link]/simple/nltk/ when looking for download links for nltk

  Getting page [need more reputation to post link]/simple/
  Could not fetch URL https://pypi.python. org/simple/: There was a problem confirming the ssl certificate: <urlopen error [Errno 1] _ssl.c:504: error:0D0890A1:asn1 encoding routines:ASN1_verify:unknown message digest algorithm>

  Will skip URL [need more reputation to post link] when looking for download links for nltk

  Cannot fetch index base URL [need more reputation to post link]

  URLs to search for versions for nltk:
  * [need more reputation to post link]
  Getting page [need more reputation to post link]
  Could not fetch URL [need more reputation to post link]: There was a problem confirming the ssl certificate: <urlopen error [Errno 1] _ssl.c:504: error:0D0890A1:asn1 encoding routines:ASN1_verify:unknown message digest algorithm>

  Will skip URL [need more reputation to post link] when looking for download links for nltk

  Could not find any downloads that satisfy the requirement nltk

No distributions at all found for nltk

Exception information:
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.3.1-py2.7.egg/pip/basecommand.py", line 139, in main
    status = self.run(options, args)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.3.1-py2.7.egg/pip/commands/install.py", line 266, in run
    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.3.1-py2.7.egg/pip/req.py", line 1026, in prepare_files
    url = finder.find_requirement(req_to_install, upgrade=self.upgrade)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.3.1-py2.7.egg/pip/index.py", line 171, in find_requirement
    raise DistributionNotFound('No distributions at all found for %s' % req)
DistributionNotFound: No distributions at all found for nltk

--easy_install installed fragments of the library and the code ran into trouble very quickly upon trying to run it.

对这个问题有什么想法吗？我真的很想得到一些反馈，告诉我如何让pip工作或者同时解决这个问题。

Answer 1

Pypi删除了对小于1.2的TLS版本的支持

你需要重新安装皮普，做

curl https://bootstrap.pypa.io/get-pip.py | python

或者对于全局Python：

curl https://bootstrap.pypa.io/get-pip.py | sudo python

Answer 2

我使用了pip版本9.0。1也有同样的问题，上面的所有答案都没有解决问题，我也因为其他原因无法用brew安装python/pip。

将pip升级到9.0。3解决了问题。因为我不能用pip升级pip，所以我下载了源代码并手动安装了它。

1. 从以下位置下载正确版本的pip-https://pypi.org/simple/pip/
2. sudopython3pip-9.0。3.焦油。gz-安装pip

curl https://bootstrap.pypa.io/get-pip.py | python

Answer 3

我发现将pypi主机指定为受信任的就足够了。示例：

pip install --trusted-host pypi.python.org pytest-xdist
pip install --trusted-host pypi.python.org --upgrade pip

这解决了以下错误：

  Could not fetch URL https://pypi.python.org/simple/pytest-cov/: There was a problem confirming the ssl certificate: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:600) - skipping
  Could not find a version that satisfies the requirement pytest-cov (from versions: )
No matching distribution found for pytest-cov

2018年4月更新：对于任何获得TLSV1_ALERT_PROTOCOL_版本错误的人：它与OP或此答案的受信任主机/验证问题无关。相反，TLSV1错误是因为您的解释器不支持TLSV1。你必须升级你的翻译。例如，见https://news.ycombinator.com/item?id=13539034, http://pyfound.blogspot.ca/2017/01/time-to-upgrade-your-python-tls-v12.html和https://bugs.python.org/issue17128.

2019年2月更新：对于一些人来说，升级pip可能就足够了。如果上述错误使您无法这样做，请使用get-pip.py.例如在Linux，

curl https://bootstrap.pypa.io/get-pip.py
sudo python get-pip.py

详情请浏览https://pip.pypa.io/en/stable/installing/.