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Python missing DLL from installed module

I got a project which consists of Python and C++. I don't understand all of it but in order to compile and run everything I run an included BAT file. I have already installed the dependencies needed. Now when I run the script, I get this:
MainProcess - [INFO] os_utils: Disabling idle sleep not supported on this OS version.
world - [ERROR] launchables.world: Process Capture crashed with trace:
Traceback (most recent call last):
File "C:\work\pupil\pupil_src\launchables\world.py", line 118, in world
from plugin_manager import Plugin_Manager
File "C:\work\pupil\pupil_src\shared_modules\plugin_manager.py", line 15, in <module>
from video_capture import Base_Manager, Base_Source
File "C:\work\pupil\pupil_src\shared_modules\video_capture\__init__.py", line 36, in <module>
from .file_backend import FileCaptureError, FileSeekError
File "C:\work\pupil\pupil_src\shared_modules\video_capture\file_backend.py", line 13, in <module>
import av
File "C:\Users\XXX\AppData\Local\Programs\Python\Python36\lib\site-packages\av\__init__.py", line 9, in <module>
from av._core import time_base, pyav_version as __version__
ImportError: DLL load failed: The specified module could not be found.
It couldn't find pyav? But if I run:
C:\Users\XXX\Downloads>pip install av-0.3.1-cp36-cp36m-win_amd64.whl
Requirement already satisfied: av==0.3.1 from file:///C:/Users/XXX/Downloads/av-0.3.1-cp36-cp36m-win_amd64.whl in c:\users\anton\appdata\local\programs\python\python36\lib\site-packages
I already have it installed. What am doing wrong here?
If I open ...site-packages\av__init__.py" I can see this:
from av._core import time_base, pyav_version as __version__
is it something here?

I suspect that the module has successfully installed, but is dynamically linked against FFMPEG. You can obtain built distributions of FFMPEG from their website (https://www.ffmpeg.org/download.html). They provide both statically linked and dynamically linked builds, though it is going to be the dynamically linked one that is providing the dll's you need. Looking at my own copy of PyAV, it seems that the current release version (3.4.2) is the one that it is linked against.
When you download it, it will have a name like ffmpeg-date-build-win64-shared. In the bin directory, you will find all the relevant DLLs. You can either add this directory to the PATH, or more easily, copy the DLLs to your python location.

sphinx python with boost-python library not found

I'm trying to use sphinx to generate documentation for a package that I wrote. Everything was working great until I added some code that used another package I wrote that wraps some boost-python modules.
Now when I run make html I get this (edited for clarity):
$ make html
sphinx-build -b html -d build/doctrees source build/html
Running Sphinx v1.3.1
loading pickled environment... done
building [mo]: targets for 0 po files that are out of date
building [html]: targets for 0 source files that are out of date
updating environment: 0 added, 1 changed, 0 removed
reading sources... [100%] my_project
/path/to/my_project/my_project/docs/source/my_project.rst:19: WARNING: autodoc: failed to import module u'my_project.my_module'; the following exception was raised:
Traceback (most recent call last):
File "/Users/harding/anaconda/lib/python2.7/site-packages/Sphinx-1.3.1-py2.7.egg/sphinx/ext/autodoc.py", line 385, in import_object
__import__(self.modname)
File "/path/to/my_project/__init__.py", line 12, in <module>
from . import module_that_uses_boost_python_classes
File "/path/to/module_that_uses_boost_python_classes.py", line 10, in <module>
import package_that_wraps_boost_python_classes
File "/path/to/package_that_wraps_boost_python_classes/__init__.py", line 21, in <module>
from native_boost_python_module import *
ImportError: dlopen(/path/to/native_boost_python_module.so, 2): Library not loaded: cpp_library.dylib
Referenced from: /path/to/native_boost_python_module.so
Reason: image not found
The problem is that when sphinx trys to import my module, it fails to load the linked c++ library from my boost-python related package. That package is installed via pip and it loads fine in all other situations.
I manually specified the full path to all the c++ libraries with install_name_tool -change and then sphinx works fine.
My question is this: how can I get sphinx to import my boost-python package without manually editing the c++ libraries manually with install_name_tool?
I have DYLD_LIBRARY_PATH set to include the directory that contains all the c++ libraries.
I'm on MacOS Sierra

Error installing pyflycapture2 on Windows

I am attempting to install this https://github.com/jordens/pyflycapture2 python binding on my Windows machine. The readme only has instructions on how to do it for Linux systems, but I imagine the library should still work.
I am able to run "python setup.py install" and it seems to successfully complete, but when I try to run "python test_flycapture2.py" I get this error:
C:\Users\clinic\Desktop\pyflycapture2>python test_flycapture2.py Traceback (most recent call last):
File "test_flycapture2.py", line 20, in <module>
import flycapture2 as fc2
File "build\bdist.win-amd64\egg\flycapture2.py", line 7, in <module>
File "build\bdist.win-amd64\egg\flycapture2.py", line 6, in __bootstrap__
ImportError: DLL load failed: The specified module could not be found.
This seems to imply that flycapture2 wasn't installed correctly. When I instead just open a python session and do "import flycapture2" I get the following error:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "build\bdist.win-amd64\egg\flycapture2.py", line 7, in <module>
File "build\bdist.win-amd64\egg\flycapture2.py", line 6, in __bootstrap__
ImportError: DLL load failed: The specified module could not be found.
Have I done something wrong with the installation process or does pyflycapture2 just not work with Windows?

A dumb solution that's worth a try. There are chances that the DLL are searched directly from where you're starting the python script. So if you have the dll somewhere on your computer, copy it along where you have your test_flycapture2.py.
But given the fact that the setup.py file has a whole bunch of absolute paths in there, I would not place my hopes too high. You can also try to install FlyCapture 2 at the exact same path, run python setup.py bdist_wheel (you will need to install wheel first with pip) in the pyflycapture2 folder, and see if that succeeds.
If it does, try installing the generated wheel (that will be in dist/ subfolder) by doing pip install dist/pyfly....wheel and test again.
Hope this helps

I'm answering this mostly because I found another post where the same question had been posted but the original problem was never answered.
How do I run an installed Python module on Windows?
In the comments, the original poster says that it suddenly started working. I found that the solution was simply to restart my computer. I have now attempted this on two computers and this worked for both of them.

ImportError: DLL load failed: The operating system cannot run %1

I want to build M2Crypto for Windows x64 to be used in python 2.7 in Windows x64.
I downloaded the library package named: "M2CryptoWin64-master" from: https://github.com/martinpaljak/M2Crypto
Then, I followed these steps from enter link description here:
In setup.py:
replace self.openssl = 'C:\pkg' by self.openssl =
'C:\grr-build\openssl' replace name = 'M2Crypto.__m2crypto' , by name
= '__m2crypto' Build:
set PATH=%PATH%;C:\grr-build\swigwin-2.0.9 C:\Python27\python.exe
setup.py build C:\Python27\python.exe setup.py install To get M2Crypto
to work for PyInstaller:
Rename C:\Python27\lib\site-packages\M2Crypto-0.21.1-py2.7-win32.egg
to C:\Python27\lib\site-packages\M2Crypto-0.21.1-py2.7-win32.egg.zip
extract M2Crypto-0.21.1-py2.7-win32.egg.zip into
C:\Python27\lib\site-packages\ without a
M2Crypto-0.21.1-py2.7-win32.egg sub directory remove
M2Crypto-0.21.1-py2.7-win32.egg.zip
When I test the library by going to Python.exe and type:
>>> import M2Crypto
I get this message:
Traceback (most recent call last): File "", line 1, in
File
"C:\Python27\lib\site-packages\m2crypto-0.22.3-py2.7-win-amd64.egg\M2Cryp
to__init__.py", line 22, in
import __m2crypto ImportError: DLL load failed: The operating system cannot run %1.
Can you please help me figure out how to solve the issue?
EDIT:
I also did the following to get M2Crypto to work for PyInstaller:
Rename C:\Python27\lib\site-packages\M2Crypto-0.21.1-py2.7-win32.egg to
C:\Python27\lib\site-packages\M2Crypto-0.21.1-py2.7-win32.egg.zip
extract M2Crypto-0.21.1-py2.7-win32.egg.zip into
C:\Python27\lib\site-packages\ without a
M2Crypto-0.21.1-py2.7-win32.egg sub directory remove
M2Crypto-0.21.1-py2.7-win32.egg.zip

Difficulties installing SOAPpy module

I am very new to python and have been figuring out how to install modules.I have been trying to install the SOAPpy module and have only had success with the required modules fpconst, wstools, and setuptools(not mentioned as required, but still ended up being required).
I am getting an error when I try and install the SOAPpy module.
Traceback <most recent call last>:
File "...\setup.py", line 43, in module <module>
__version__ = load_version()
File "...\setup.py", line 35 in load_version
execfile(filename, d.__dict__)
IOError: [Errno 2] Unable to load the version number (no such file or directory):
'...\\src\\SOAPpy\\version.py'
Not sure what i should do to fix this.
Any help is greatly appreciated!

Looking at SOAPpy's setup.py file, it tries to import SOAPpy.version. This doesn't work if you're calling it from somewhere else. Try running it directly in the SOAPpy directory because Python adds your current working directory to sys.path. For example:
cd C:\Users\eclaird\Download\SOAPpy\ # The folder with setup.py
python.exe setup.py install

Thanks for the help.
I eventually found what the issue was. I had to get some other required modules for the install to work, also the tar file I got was missing directories, so I found the completed version on Github.