pip issue installing almost any library

Question

I have a difficult time using pip to install almost anything. I'm new to coding, so I thought maybe this is something I've been doing wrong and have opted out to easy_install to get most of what I needed done, which has generally worked. However, now I'm trying to download the nltk library, and neither is getting the job done.

I tried entering

sudo pip install nltk

but got the following response:

/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.

Any thoughts on this issue? I'd really appreciate some feedback on how I can either get pip working or something to get around the issue in the meantime.

Answer 1

I did the following on Windows 7 to solve this problem.

c:\Program Files\Python36\Scripts> pip install beautifulsoup4 --trusted-host *

The --trusted-host seems to fix the SSL issue and * means every host.

Of course this does not work because you get other errors since there is no version that satisfies the requirement beautifulsoup4, but I don't think that issue is related to the general question.

Answer 2

I found it sufficient to specify the pypi host as trusted. Example:

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

This solved the following error:

  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

Update April 2018: To anyone getting the TLSV1_ALERT_PROTOCOL_VERSION error: it has nothing to do with trusted-host/verification issue of the OP or this answer. Rather the TLSV1 error is because your interpreter does not support TLS v1.2, you must upgrade your interpreter. See for example https://news.ycombinator.com/item?id=13539034, http://pyfound.blogspot.ca/2017/01/time-to-upgrade-your-python-tls-v12.html and https://bugs.python.org/issue17128.

Answer 3

You can also use conda to install packages: See http://conda.pydata.org

conda install nltk

The best way to use conda is to download Miniconda, but you can also try

pip install conda
conda init
conda install nltk

Answer 4

Just uninstall and reinstall pip packages it will workout for you guys.

Mac os version: high Sierra 10.13.6

python version: 3.7

So I uninstalled the older pip and installed the newest version10.0.0 by entering this:

python3 -m pip uninstall pip setuptools

curl https://bootstrap.pypa.io/get-pip.py | python3

Now my problem was solved. If you are using the python2, you can substitute the python3 with python. I hope it also works for you.

Answer 5

To install any other package I have to use the latest version of pip, since the 9.0.1 has this SSL problem. To upgrade the pip by pip itself, I have to solve this SSL problem first. To jump out of this endless loop, I find this only way that works for me.

1. Find the latest version of pip in this page: https://pypi.org/simple/pip/
2. Download the .whl file of the latest version.
3. Use pip to install the latest pip. (Use your own latest version here)

sudo pip install pip-10.0.1-py2.py3-none-any.whl

Now the pip is the latest version and can install anything.

Answer 6

Use Latest version of python on mac Python 2.7.15rc1 https://bugs.python.org/issue17128