ImportError: Permission Denied while using LXML - python

I've been having a ton of trouble using LXML, after installing it from https://pypi.python.org/pypi/lxml/3.2.1 using Easy_Install-2.7. I installed it on Windows using cygwin, and at first the package seemed to be okay. However upon further testing I ran into problems.
When I run code with:
import lxml
it works completely fine. But as soon as I try:
import lxml.etree
I get this error:
Traceback (most recent call last):
File "D:\Nick_Code\NewsScraper\testdummy.py", line 7, in <module>
import lxml.etree
File "/usr/lib/python2.7/site-packages/lxml-3.2.0-py2.7-cygwin-1.7.20-i686.egg/lxml/etree.py", line 7, in <module>
__bootstrap__()
File "/usr/lib/python2.7/site-packages/lxml-3.2.0-py2.7-cygwin-1.7.20-i686.egg/lxml/etree.py", line 6, in __bootstrap__
imp.load_dynamic(__name__,__file__)
ImportError: Permission denied
I've been trying to find information/work arounds for quite a while but no success. Please let me know if you have any insight or need information.
Thanks!
Michael

This is not a solid answer. But I will highlight several of the problems involved for obtaining a solution. Most likely the problem above, is like a cancer caused by several factors acting catastrophically together.
I have the same exact problem as in the OP, when attempting to use the native Cygwin supplied Python packages on my Windows Vista machine. Being new to Python I have spent several days in trying to get this to work, and understand why it is not working. But all my Google-fu returned nothing but countless dead ends. So here's my take on this.
There are many reasons why Python could have trouble under Cygwin, some which you can do something about and some which are beyond most peoples control. What it boils down to, are the following key issues:
Windows is a complete mess when it comes to file permissions, and Cygwin cannot handle windows file permissions very well. So what you see in Cygwin is far from the whole story.
Windows is shamefully character case-independent which causes loads of trouble, especially when you need to (cross)compile anything that was originally developed under *nix based system (i.e. everything). In fact, if you attempt extracting any archive that contains files whose names differ only in capitalization. (I.e. "makefile" vs "Makefile" etc.) files under Windows or Cygwin, you loose all but one of the files. in case their You need to enable case-sensitivity to do anything more than "hello world" *nix compilations.
Windows handles symlinks completely different than Cygwin. And if your ZIP, TAR etc. archives contain any symlinks, they will be broken after extraction to Windows environment.
Sloppy code practices, where developer have not properly tested their creations on various environments, or carefully set proper file permissions to their *.tar.gz collections. Including correct dependency specifications, or mentioning whether or not binaries has been statically linked etc.
For the full gory details and further (Win-Cygwin) issues, look HERE.
At first I tried to use Cygwin's own Python without any additional packages, and nstalling lxml using PIP and easy_install. Then I tried to use Cygwin's own libxml2, libxslt and xml python packages, and I had the same problems.
At first, after installing the static windows binaries (as suggested elsewhere),
I got this error:
File "/usr/lib/python2.7/site-packages/lxml-3.2.4-py2.7-cygwin-1.7.24-i686.egg/lxml/etree.py", line 6, in __bootstrap__
imp.load_dynamic(__name__,__file__)
ImportError: Permission denied
Aborted (core dumped)
Then I investigated the file permissions and changed those with: chmod -R 755 /usr/lib/python2.7/
I got one step further to isolate problem to an apparently missing file.
And enabling verbose and diagnostic mode's didn't help much either.
File "/usr/lib/python2.7/site-packages/lxml-3.2.4-py2.7-cygwin-1.7.24-i686.egg/lxml/etree.py", line 6, in __bootstrap__
imp.load_dynamic(__name__,__file__)
ImportError: No such file or directory
Aborted (core dumped)
HERE is the exact statement specification:
Load and initialize a module implemented as a dynamically loadable shared
library and return its module object. If the module was already initialized, it
will be initialized again. Re-initialization involves copying the __dict__
attribute of the cached instance of the module over the value used in the module
cached in sys.modules. The pathname argument must point to the shared library.
The name argument is used to construct the name of the initialization function:
an external C function called initname() in the shared library is called. The
optional file argument is ignored. (Note: using shared libraries is highly
system dependent, and not all systems support it.)
So I started reading on the lxml website which clearly state lxml's dependencies on both libxml2 and libxslt, and unless they are statically linked, they also depend on iconv and zlib. So you're lead to believe you need to install all of these. Don't! Continue reading. But if you're going to build from sources (as easy_install may try to do) you'll need everything, including the development header libraries: libxml2-devel, libxslt-devel. Another place states that you also need Cython and install with:
easy_install lxml==dev
The dependencies are shown in this picture from HERE:
So you think you may get away with something like:
STATIC_DEPS=true pip install lxml
But that doesn't do it either. Probably because the libraries used to compile Cygwin's Python have to be the same as those for compiling lxml. But I don't know. Notice how the lxml package refers to Cygwin "1.7.24". My Cygwin is already "1.7.25" and you can check this with uname -a. Then you can check your static python executable with file and ldd. Then you understand that this also depend on the C-compiler used for building python/cygwin under Windows or *nix. Smelling a nightmare I decided that building my own was not the way to go. So next I tried to install the Python libraries (supplied as
executables) meant for Windows Python. This didn't work since I never had windows native Python installed, and I was greeted with an error that the installed could not find Python in my registry. I could of course just extract the executable, but I wouldn't know where to put the binaries without the installer. So I had another idea...
There are 3 possible solutions to getting this to work, as far as I can see.
The easy way of installing a Windows native Python interpreter. You loose some native Cygwin functionality, unless you install in correct place: /usr/lib/python2.7 and make sure Cygwin can find it and use it. This also uses a different file-permissions, case-sensitivity and character set (UTF-16LE) than Cygwin (UTF-8), potentially creating many other issues down the line! Difficulty: Easy
Continue hacking the Cygwin's Python, to make it work with the binary libraries used in (1). But this requires:
a) Uninstall and remove all Cygwin Python packages, except bare Python interpreter.
b) Remove all PIP and easy install traces.
c) Hacking the Windows registry to pretend to have Python27 installed:
HKEY_LOCAL_MACHINE\SOFTWARE\Python\PythonCore\2.7\InstallPath C:\Python27\
HKEY_LOCAL_MACHINE\SOFTWARE\Python\PythonCore\2.7\PythonPath C:\Python27\Lib;C:\Python27\DLLs;C:\Python27\Lib\lib-tk
HKEY_CLASSES_ROOT...
d) Install the Windows binary libraries.
e) All the rest should now hopefully work with PIP or easy_install. Difficulty: Medium!
Doing it properly by compiling Python and all libraries from scratch. Difficulty: Hard!
I successfully did (1), but I still think (2) is the smarter way of doing it, but I have not tested it, which is why I don't consider this as a good answer. BTW. One more quirk, I have to run the interpreter with: python.exe -E to avoid an annoying: "SyntaxError: invalid syntax" when hitting return!
Conclusion:
Apparently, you don't need the libxml2 and libxslt python packages to use lxml!
In my case I needed Scrapy, so I also had to install a few other packages.
$ pip.exe list
cssselect (0.9.1)
lxml (3.2.4)
pip (1.4.1)
pyOpenSSL (0.11)
pywin32 (218)
queuelib (1.1.1)
Scrapy (0.20.0)
setuptools (1.4.1)
six (1.4.1)
Twisted (13.2.0)
w3lib (1.5)
zope.interface (4.0.5)
$ll /cygdrive/c/Python27/Lib/site-packages/
adodbapi
cssselect
isapi
lxml
OpenSSL
pip
pythonwin
pywin32_system32
queuelib
scrapy
twisted
w3lib
win32
win32com
win32comext
zope
cssselect-0.9.1-py2.7.egg-info
lxml-3.2.4-py2.7.egg-info
pip-1.4.1-py2.7.egg-info
queuelib-1.1.1-py2.7.egg-info
Scrapy-0.20.0-py2.7.egg-info
six-1.4.1-py2.7.egg-info
Twisted-13.2.0-py2.7.egg-info
w3lib-1.5-py2.7.egg-info
zope.interface-4.0.5-py2.7.egg-info
PyWin32.chm
setuptools-1.4.1-py2.7.egg
pyOpenSSL-0.11-py2.7.egg-info
pywin32-218-py2.7.egg-info
easy-install.pth
pywin32.pth
setuptools.pth
zope.interface-4.0.5-py2.7-nspkg.pth
pythoncom.py
six.py
pythoncom.pyc
six.pyc
pythoncom.pyo
pywin32.version.txt
README.txt
Useful References:
HERE
HERE
HERE HERE HERE HERE
HERE

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RDKit could be a nice package if it wasn't so complicated to install.
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However, on different operating systems or different environments.
My configuration is:
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On the webpage it says:
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So, then I tried some unofficial binaries of RDKit.
If I unpack them and set the paths according to instructions, I get this error message:
>>> from rdkit import Chem
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Users\xyz\Programs\RDKit\rdkit\__init__.py", line 2, in <module>
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So, finally my questions:
How to properly install RDKit with the above mentioned configuration?
What is the specified DLL which is missing?
Where is it expecting it and searching it?
Are these RDKit 3.6 binaries maybe incompatible with Python 3.7.4?
I'm pretty sure it is probably a "small" thing (a path here or a check there), but I'm stuck. Thank you for any hints.
Update:
Apparently, it is not just a "small" thing. Chances to get this to work are most likely very low.
In the meantime I found this:
https://github.com/rdkit/rdkit/issues/1812
https://github.com/rdkit/rdkit/issues/2389
If the author of rdkit writes (April 2019):
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to the best of my knowledge no one has managed to figure out how to
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I'd be happy to accept a PR from someone who has figured this out, but
I am not likely to have the time to do this myself anytime in the near
future.
So, if anybody feels capable achieving this, please feel free.
I will invest time in something else or will have to switch to Anaconda if I want to use RDKit.
On the webpage you linked there is a section about missing DLLs:
"In Win7 systems, you may run into trouble due to missing DLLs, see one thread from the mailing list: http://www.mail-archive.com/rdkit-discuss#lists.sourceforge.net/msg01632.html You can download the missing DLLs from here: http://www.microsoft.com/en-us/download/details.aspx?id=5555"
Not sure if this helps

Installing and running pypy on linux

I have been attempting to install and run pypy3 on a linux machine but am running into troubles. I have been using pypy on a mac but installed it using homebrew so didn't encounter any of these troubles.
I downloaded the most recent build and unpacked the tar file as described by their documentation. I followed the steps exactly (except replacing pypy with pypy3 and using the appropriate file name). However, when typing
./pypy3-v6.0.0-linux64/bin/pypy3
I get the following error:
./pypy3-v6.0.0-linux64/bin/pypy3: error while loading shared libraries: libbz2.so.1.0:
cannot open shared object file: No such file or directory
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If 'pypy3' is not a typo you can use command-not-found to lookup the package that
contains it, like this:
cnf pypy3
But cnf pypy3 only confirms that the pypy3 is not found.
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Those distributions are for debian linux only. You may have better luck with the portable binaries if the ones provided by OpenSuse are too old for you.
Edit: note that you used a link to an old version of the documents, you should have looked here which states "These builds depend on dynamically linked libraries that may not be available on your OS"

How to make downloaded Python libs work on Windows?

I got this simple problem and I can't find the answer anywhere, I'm wasting a lot of time!
I did a Python programm on Linux (which works OK), but when I try to run it on Windows, there are too problems with libs...
I have installed the libs I need (dateutil, lxml, xmlrpclib...) in C:\Python34\Lib\site-packages. But then, they don't work as they do on Linux. For example:
from dateutil.tz import tzlocal
Gives me next error:
File "C:\Python34\lib\site-packages\dateutil\tz.py", line 9, in module
from six import string_types, PY3 ImportError: No module named 'six'
That is, they are not finding the other modules... why???
Have you try this ?
http://www.instructables.com/id/How-to-install-Python-packages-on-Windows-7/
Maybe it can help
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There are some packages that need to be compiled. This can be difficult on Windows 7 if you don't have the proper toolchain set up to compile packages. I'd recommend Christoph Gohlke's wonderful collection of installable packages for Windows. You just need to make sure to grab the right version. Since 3.4 is still relatively new, some packages may not be available, so be warned.

Best practice for upgrading Python modules

I've been learning Python for several months but now finding some problems with my 2.7 installation as I've looked into modules such as nltk.
However, when I want to list modules using help ("modules) I have the main error which I think explains the problem is:
/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/distribute-0.6.28-py2.7.egg/setuptools/command/install_scripts.py:3: UserWarning: Module numpy was already imported from /Library/Python/2.7/site-packages/numpy-override/numpy/__init__.pyc, but /Library/Python/2.7/site-packages/numpy-1.8.0.dev_5c944b9_20120828-py2.7-macosx-10.8-x86_64.egg is being added to sys.path
from pkg_resources import Distribution, PathMetadata, ensure_directory
I also receive the following error to do with deprecated modules:
/Library/Python/2.7/site-packages/statsmodels-0.5.0-py2.7-macosx-10.8-intel.egg/scikits/statsmodels/__init__.py:2: UserWarning: scikits.statsmodels namespace is deprecated and will be removed in 0.5, please use statsmodels instead
I'm still trying to get to grips with paths. How can I avoid this issue in future?
You have installed packages under your operating system Python library. This is big no no. What you should have done is to create an isolated, disposable, Python environment with virtualenv tool:
http://opensourcehacker.com/2012/09/16/recommended-way-for-sudo-free-installation-of-python-software-with-virtualenv/
This way, when you upgrade your packages or need to get rid of them you can always reset the state of all of your Python packages by simply deleting the environment and creating new one.
Python packages installed via pip or easy_install commands are easy to install, but impossible to uninstall...
But when the damage has already happened you nede to manually try to clean up /Library/Python/2.7/site-packages/ by deleting files by and trying not to destroy your system Python in the process.

Has anybody been able to install PyWeka?

I need to install in python 2.6 or 2.7 for windows the library PyWeka0.3dev, It says it requires setuptools, which I installed but then they told me it was a deprecated instalation library and I installed distribute, then I downloaded the PyWeka compressed package and each time I try to install it neither with setup.py nor with easy_install (where it says something like no module ez_setup). Can anybody give me a clue about how to do this?
As mentioned to you via Aardvark (yes, I am omnipresent), the module in question is broken. You can't easy_install it. It's a bug in PyWeka.
You can download the file from PyPI, http://pypi.python.org/pypi/PyWeka/0.3dev, and unpack it.
In the file setup.py, remove the following two lines:
from ez_setup import use_setuptools
use_setuptools()
And install it by running
python setup.py install
You need to have installed numpy and NamedMatrix (which has the same bug as PyWeka) first.
However, you mentioned you are on Windows. I strongly doubt that PyWeka will work on Windows. There are some Unix specific code in it.
And I still really want to know why the authors are reading files by calling cat from subprocess. That seems pretty pointless and is together with the broken install, good enough reason for me to keep far away from that module. I suspect it's authors simply have no idea what they are doing.
That, or they are geniuses.
A punk/goth approach to programming probably has the right to be..
To get the C-compliation part to work on windows you either need (1) to have Visual Studio of the same version that was used to compile the python version you are using, or (2) mingw which is a bit trickier to set up.

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