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KeyError: 'vendor_id' when installing packages

I am attempting to carry out lens correction and I've fallen at the first hurdle. After running the following code, I receive this error...
#Install required packages
!pip install opencv-python
import cv2
import numpy as np
import pathlib
!pip install chessboard
from chessboard import calibrate_chessboard
from utils import load_coefficients, save_coefficients
KeyError Traceback (most recent call last)
<ipython-input-19-0a40b3424bef> in <module>()
6 import pathlib
7 get_ipython().system('pip install chessboard')
----> 8 from chessboard import calibrate_chessboard
9 from utils import load_coefficients, save_coefficients
2 frames
/usr/local/lib/python3.7/dist-packages/chessboard/benchmark.py in Benchmark()
105 ('machine', platform.machine()),
106 # CPU.
--> 107 ('cpu_vendor', cpu_info['vendor_id']),
108 ('cpu_model', cpu_info['brand']),
109 ('cpu_freq_actual', cpu_info['hz_actual'][0]),
KeyError: 'vendor_id'
Can anyone help with this please?

It looks like that you are using outdated package chessboard, not updated since 2017, repo now archived.
It rely on another package py-cpuinfo. There is this issue. The key vendor_id is now replaced with vendor_id_raw. Note that setup.py for chessboard does not specify version for py-cpuinfo, so I guess you use the latest one.
One way to solve the problem is to use specific older version of py-cpuinfo before that change. The latest version of py-cpuinfo with vendor_id is 5.0.0. The latest version before latest chessboard release date is 3.3.0
Another option is to try and replace key vendor_id with vendor_id_raw everywhere inside chessbeoard package.
My preference would be with the second option as chessboard is no longer developed. In any case be aware there might be other issues or unwanted behaviour.

Installing OCRmyPDF on Windows Server 2016 - Can't find liblept.dll. Is editing Path safe?

I'm trying to import ocrmypdf on my company's client's Windows Server 2016 Build 14393 computer using Python 37-32. When I import the library, in a Jupyter Notebook, it is unable to locate leptonica by using ctypes.utility.find_library().
Ocrmypdf is a Linux-developed Python 3 package. Per the documentation (https://ocrmypdf.readthedocs.io/en/latest/introduction.html) it does not support Windows. The suggested workarounds are a docker container and Windows Subsystem for Linux.
I would rather not use a docker container as neither I nor my coworkers are very experienced with it. I am unable to use wsl as it is not available for my build of Windows Server 2016 (see the troubleshoot subsection: https://learn.microsoft.com/en-us/windows/wsl/install-on-server)
This discussion (find_library() in ctypes) states that you can point ctypes.utility.find_library to the needed library file by editing the environment Path variable to be a folder which includes it. Conveniently, Tesseract OCR's windows download includes liblept. Would editing the Path variable to point toward that folder be a dangerous thing to do?
Edit: I tried adding the path to Tesseract-OCR's folder on my laptop's environment Path and restarted Anaconda, etc. ocrmypdf still gave the same error.
A closer read of that discussion brought up the point that find_library operates differently on Windows. A read of the documentation (https://docs.python.org/2.5/lib/ctypes-finding-shared-libraries.html) states that "On Windows, find_library searches along the system search path, and returns the full pathname, but since there is no predefined naming scheme a call like find_library("c") will fail and return None." Does this mean I have to hardcode in a name to use in order to find the library?
This issue has been replicated, albeit on a different machine, here: https://github.com/jbarlow83/OCRmyPDF/issues/341. You can reproduce the issue by running the below code on a Windows machine.
!pip install ocrmypdf
import ocrmypdf
The expected result of the above code is that ocrmypdf is successfully imported in a usable form.
The result of the above code is:
OSError Traceback (most recent call last)
<ipython-input-2-a81f3474d7ad> in <module>
----> 1 import ocrmypdf
~\AppData\Local\Continuum\anaconda3\lib\site-packages\ocrmypdf\__init__.py in <module>
16 # along with OCRmyPDF. If not, see <http://www.gnu.org/licenses/>.
17
---> 18 from . import helpers, hocrtransform, leptonica, pdfa, pdfinfo
19 from ._version import PROGRAM_NAME, __version__
20 from .api import Verbosity, configure_logging, ocr
~\AppData\Local\Continuum\anaconda3\lib\site-packages\ocrmypdf\leptonica.py in <module>
40 logger = logging.getLogger(__name__)
41
---> 42 lept = ffi.dlopen(find_library('lept'))
43 lept.setMsgSeverity(lept.L_SEVERITY_WARNING)
44
OSError: cannot load library '<None>': error 0x57

I have been able to get this working Windows 10 by updating the path and it works fine. I used msys2 to install it, hence, the path name. Update to point where your liblept-5.dll is located.
if os.name == 'nt':
os.environ['PATH'] = os.environ.get("PATH", "") + ';C:\\msys64\\mingw64\\bin'

Problem with importing rospy and roslib libraries

I am new to ROS and python. This question could be silly but spent almost 5 hours on this. I am using PyCharm (Latest version) with Python 2.7.15 64 bit (Also tried with 3.x). I need to import a few libraries as below:
import roslib;
roslib.load_manifest('smach_tutorials')
import rospy
import smach
import smach_ros
However, PyCharm fails to identify roslib, rospy, smach and smach_ros (could not find in the interpreter also to import). The above libraries are example given in the official site:
http://wiki.ros.org/smach/Tutorials/Simple%20State%20Machine
OS: Windows 7 (64 bit)
ROS not installed: ("SMACH is a ROS-independent Python library to build hierarchical state machines" - from the official site)
Error Traceback:
Traceback (most recent call last):
File "C:/Users/****/Desktop/Python/TestCharm.py", line 3, in <module>
import roslib;
ModuleNotFoundError: No module named 'roslib'

If you are using the catkin version of ROS (Groovy and later), it does not use the manifest file but uses the package.xml file instead.
So your code will be:
import rospy
import smach
Apparently, your code is ready for ROS Fuerte or earlier version.
With supposing that Smach is ROS-independent, you need only to the import smach

Thanks for all the support. I found out it is not possible for my perticular case to use SMACH because it has dependency on catkin. I am using Windows 7 and should be upgraded to windows 10 or use Ununtu Linux.

Pytables on Enthought Python for OS X 10.8.2

I've been struggling to get pytables and the underlying HDF5 library working on python in OS X, so thought I'd give the Enthought distribution a go (which will also greatly simplify deployment across platforms later on).
I installed EPD 7.3 for 64-bit OS X (I'm running 10.8.2), but unfortunately no success, I get the following when trying to load the pytables...
In [4]: import tables
--------------------------------------------------------------------------- ImportError Traceback (most recent call last) /<ipython-input-4-389ecae14f10> in <module>()
----> 1 import tables
/Users/davidperry/Library/Python/2.7/lib/python/site-packages/tables/__init__.py in <module>()
57
58 # Necessary imports to get versions stored on the Pyrex extension
---> 59 from tables.utilsExtension import getPyTablesVersion, getHDF5Version
60
61 __version__ = getPyTablesVersion()
ImportError: dlopen(/Users/davidperry/Library/Python/2.7/lib/python/site-packages/tables/utilsExtension.so, 2): Symbol not found: _SZ_BufftoBuffCompress Referenced from: /Users/davidperry/Library/Python/2.7/lib/python/site-packages/tables/utilsExtension.so Expected in: flat namespace in /Users/davidperry/Library/Python/2.7/lib/python/site-packages/tables/utilsExtension.so
I presume this means that szip, a required library for HDF5, cannot be found? If it is actually missing from EPD (seems odd...), can I install it myself without building HDF5 from source? Or is is just in a strange place?

First, I apologize for the problems you are encountering.
It looks as if you are not loading pytables from EPD, but from a former installation. How does PYTHONPATH look like in your environment ?
Generally, EPD is installed somewhere in /Library/Frameworks/Python.framework/Versions/7.3. What does the following do ?
PYTHONPATH= /Library/Frameworks/Python.framework/Versions/7.3/bin/python -c "import tables; print tables.__version__"
or (64 bits version):
PYTHONPATH= /Library/Frameworks/EPD64.framework/Versions/7.3/bin/python -c "import tables; print tables.__version__"
It should return you something like "2.3.1" (the actual tables version available in EPD). If that indeed works, then do make EPD the default python in your environment, you will need to adapt the PATH/PYTHONPATH variables to make it available.
If that still does not work, then can you try the following (adapt for 32 bits):
PYTHONPATH= /Library/Frameworks/EPD64.framework/Versions/7.3/bin/python -c "import sys; print sys.path"
and paste the output ?

wxPython import error

I'm having trouble figuring out an error message in Python.
yesterday, I've installed python using the latest EPD package, and wxPython2.9 using the wxPython2.9-osx-cocoa-py2.7 package for Mac OS.
I then added wx to my PYTHONPATH.
export WXDIR=/usr/local/lib/wxPython-2.9.1.1/lib/python2.7/site-packages/wx-2.9.1-osx_cocoa
export PYTHONPATH=$WXDIR
export PYTHONPATH=$PYTHONPATH:$WXDIR/tools
but when I try to run stuff I get this error:
In [14]: import matplotlib.pyplot
---------------------------------------------------------------------------
ImportError Traceback (most recent call last)
/Users/imrisofer/Documents/third/hddm-read-only/hddm/<ipython console> in <module>()
/Library/Frameworks/EPD64.framework/Versions/7.0/lib/python2.7/site-packages/matplotlib/pyplot.py in <module>()
93
94 from matplotlib.backends import pylab_setup
---> 95 new_figure_manager, draw_if_interactive, show = pylab_setup()
96
97 #docstring.copy_dedent(Artist.findobj)
/Library/Frameworks/EPD64.framework/Versions/7.0/lib/python2.7/site-packages/matplotlib/backends/__init__.py in pylab_setup()
23 backend_name = 'matplotlib.backends.%s'%backend_name.lower()
24 backend_mod = __import__(backend_name,
---> 25 globals(),locals(),[backend_name])
26
27 # Things we pull in from all backends
/Library/Frameworks/EPD64.framework/Versions/7.0/lib/python2.7/site-packages/matplotlib/backends/backend_wxagg.py in <module>()
21
22 from backend_agg import FigureCanvasAgg
---> 23 import backend_wx # already uses wxversion.ensureMinimal('2.8')
24 from backend_wx import FigureManager, FigureManagerWx, FigureCanvasWx, \
25 FigureFrameWx, DEBUG_MSG, NavigationToolbar2Wx, error_msg_wx, \
/Library/Frameworks/EPD64.framework/Versions/7.0/lib/python2.7/site-packages/matplotlib/backends/backend_wx.py in <module>()
43 import wxversion
44 except ImportError:
---> 45 raise ImportError(missingwx)
46
47 # Some early versions of wxversion lack AlreadyImportedError.
ImportError: Matplotlib backend_wx and backend_wxagg require wxPython >=2.8
I can successfully import wx, so I don't no what's the problem.
Am I missing anything in the PYTHONPATH?

In Ubuntu 12.04, this problem can be solved by running the command
sudo apt-get install libjpeg62
I realize this may not be useful here, but I wanted to document it somewhere on teh interwebz so I can find it when I run into this problem again myself which will undoubtedly happen.

I'm using Ubuntu 13.10, Canopy 1.2, and PyCharm 3.0.2. When trying to use matlablib, it always complains "Matplotlib backend_wx and backend_wxagg require wxPython >=2.8".Pretty sure that I'm using wxPython 2.8. Then I tried all the methods described in this page, but neither of them works for me.
It turns out that it can be solved by modifying matplotlibrc file. There is a line:
backend : WXAgg
In fact we can change the backend to whatever we like, and I change it to TKAgg, which works just fine for me.

Select your wx version before importing any wx modules
import wxversion
wxversion.select('2.8')
The above code should come before import wx

This happened to me on a Windows x64 installation that did not install wxversion.py in the site-packages directory (c:\Python27\Lib\site-packages by default).
You can get a copy of wxversion.py from the WX svn repository:
http://svn.wxwidgets.org/viewvc/wx/wxPython/trunk/wxversion/wxversion.py?content-type=text%2Fplain&view=co

this link helped me
https://support.enthought.com/entries/22601196-wxPython-2-8-and-2-9
Here's how I fixed the problem, which I hope will be useful for others in future
In Terminal: gedit Enthought/Canopy_64bit/User/lib/python2.7/site-packages/matplotlib/mpl-data/matplotlibrc
Edit the line "backend : WXAgg" into "backend : QtAgg"
Save and exit

I just ran into this myself. One potential cause of this (quite unhelpful) error message is if you installed wx as a single-version installation (INSTALL_MULTIVERSION=0 when running setup.py). In this case, the module wxversion does not get built (or installed) and as such matplotlib incorrectly assumes that all of wx is missing.
This currently is the default setting in installations by the homebrew version of wxWidgets (wxmac) with the option --python.
In your case (albeit a year and a half late), you'd need to ensure that wxversion.py exists within /usr/local/lib/wxPython-2.9.1.1/lib/python2.7/site-packages/. If it doesn't, you'd need to recompile wx with the above flag set. Otherwise you just need to set your $PYTHONPATH such that it includes the base site-packages directory, too:
export WXDIR=/usr/local/lib/wxPython-2.9.1.1/lib/python2.7/site-packages
export PYTHONPATH=$WXDIR:$WXDIR/wx-2.9.1-osx_cocoa:$WXDIR/wx-2.9.1-osx_cocoa/tools

I've solved with this:
defaults write com.apple.versioner.python Prefer-32-Bit -bool yes

I solved this by setting the backend to MacOSX in ~/.matplotlib/matplotlibrc:
backend : MacOSX

I've solved this on Windows by looking in the site packages folder in the python library. In there, there should be another folder titled site-packages. In this subfolder, there is the wxversion library. If you copy this library into the Lib folder in python, this import error should be averted.

sudo apt-get install python-wxtools
Install it. Worked for me.