A noob python question.
I have a package called TorCtl, I saved it in /root/A and create a file (useIt.py) in /root/A which uses the package and it works absolutely fine.
now the problem starts when I try to use this package within another project.
I copied TorCtl package into /root/B/C and created a new file (useIt2.py) (this file is used from another file that is the main for this package.)
when I run main I get import error from TorCtl package. for example:
from elixir import *
ImportError: No module named elixir
I have no idea why it should work in one folder and not another.
Can anyone point out what I am doing wrong please?
Related
I am learning Python using python programming for the absolute beginner 3rd ed. Now in Chapter 9, When I coded a module called games (games.py file) in the project root directory, and tried to import it in another file called simple_game.py (which is also created in the same directory as games.py) using
import games
Python simply stated ImportError: No module named 'games'. I am wondering how to solve the issue in PyCharm (I am using it to do all the practises with the book).
PS. I am using Python 3.4.2 on Win 8.1 X64 with PyCharm 4.0.4.
[EDIT] I created another games.py by right-clicked the project folder and chose New->Python File and copy the code in the old games.py to the new one. Run simple_game and the import issue was gone. I guess it has something to do with how you create a python file in the project? As I usually just right-clicked the project folder and choose New->File and Register New File Type Association as Python files. This way, I found the python files in the project folder are unrecognized (shown as File for Type) if I checked them in the project directory. Also, don't forget to mark project folder as Sources Root in order to make the module name reference work.
thanks
I'm following a tutorial to call python code from a C++ program from the python docs.
Everything works just fine when trying to call the multiply example. Now if I add a line to the python source code importing a library, lets say openpyxl,
from openpyxl import load_workbook
I receive an error from python
ImportError: No module named openpyxl
I thought if I import a system library, I wouldn't have any problems, but I also get an error if I try to import datetime.
I don't have any error if I import the file from the python console. The openpyxl library is installed in my system.
So my question is: how to import python source code that needs to import packages?
EDIT: Ok, I forgot to mention something, I have not been completely honest with you guys, I'm sorry.
Trying to run the example I run into a problem: I couldn't make python found my multiply.py file, and the line PyImport_Import always return null.
My solution was to add the path in which I knew my python source was by using PySys_SetPath. The problem is that I just realized that this function doesn't append a new directory, it just overwrites the PYTHONPATH. So now python can find multiply.py, but absolutly anything else.
Of course I've deleted that line but now I have another question, why does python can't find my source if the file is just in the same directory of the C++ compiled program?
The I realized that my sys.path from my python console was a little different from the path showed in my embedded python: the first one had at the beginning of the list an empty string ''. I'm not a python expert, but when I add that line to my path I could import the multiply.py so it seems that was the reason I couldn't import modules that were located to relative to my executable was the missing of this empty path -but still don't know what it means-.
I have to thank to #paul-evans who give me the idea of adding the path to find my files.
This is what PYTHONPATH is for. You can set it as an environment variable containing a list module directories, or in the code itself something like:
import sys
sys.path.append("path/to/openpyxl/module")
Let's say I have vtk module in my Python site packages, and from application with own Python distribution I want to access this module.
I tried couple of things like:
import sys
sys.path.append("C:\Python27\Lib\site-packages")
sys.path.append("C:\Python27\Lib\site-packages\vtk")
import vtk
lut = vtk.vtkLookupTable()
but it fails to load module properly:
AttributeError: 'module' object has no attribute 'vtkLookupTable'
If I do same from default Python interpreter all is fine.
Now I thought to make a wrapper of vtk in this application site packages, with simple __init__.py resolving paths, so that when I do import vtk it will hopefully load right thing, but I have no experience with Python packages to try to make this work
To put it simple, how can I wrap module from arbitrary folder, in Python site packages by making folder with same name as referenced package and simple __init__.py file?
Remove these lines:
sys.path.append("C:\Python27\Lib\site-packages")
sys.path.append("C:\Python27\Lib\site-packages\vtk")
The site-packages will already be on your python path. Adding a package/folder within that python path (especially at the first level), will just mess with your imports. How is this vtk package structured?
/path/to/site-packages/
vtk/
__init__.py
vtk.py
In this case, to access a function within vtk:
from vtk import vtk
lut = vtk.vtkLookupTable()
It all comes down to how the folder is arranged. You could also do this:
import vtk
lut = vtk.vtk.vtkLookupTable()
Do not try to hack python importing by creating proxy modules simply because you're not understanding how python importing is working. The error was quite clear. The attribute vtkLookupTable did not exist on whatever it was you imported. You imported the wrong thing. Fix it.
You should very very very very rarely have to manipulate the sys.path manually. When you do have to, you should know that it's the right reason - not to work around something you're not fully understanding.
I had trouble with python paths when I first started with python. It can be frustrating, but coming to understand how it works is necessary. What can help you is something like the following:
import vtk
print dir(vtk)
That will print the attributes of vtk, so you can explore exactly what is in the package or module in cases like this where you think you're importing the right thing.
After re-reading your question, it seems like this is a different python install you're talking about. The answer is to install this package into the other python install, or include this package as a top level import by copying the folder into the root level of your application.
"C:\Python27\Lib\site-packages" is already on your python path. So appending path is unnecessary. Remove:
import sys
sys.path.append("C:\Python27\Lib\site-packages")
sys.path.append("C:\Python27\Lib\site-packages\vtk")
Create a new folder called 'vtk\' in "C:\Python27\Lib\site-packages", then create a new python file named __init__.py in "C:\Python27\Lib\site-packages\vtk" and put your own module vtk.py in this directory.
Using:
import vtk
or
from vtk import vtk
to use your own module.
My situation is similar to one in this question... The difference is,
In our python/django project, we have a directory called utils, which keeps basic functions...
Sometimes, we need to test some modules by running thm from console like
python myproject/some_module.py
It is all good, until python tries to import something from our utils directory...
from utils.custom_modules import some_function
ImportError: No module named custom_modules
I check my python path, and our project is on the list, each folder under the project file has __init__.py files, and when i run ipython within project directory... Everything is ok, otherwise, python imports from its own utils directory...
My collegues use the sama method without any problem, but it throws ImportError on my environment... What could be the problem that all of us was missing?
UPDATE: My project directory, and each sub-drectory have __init__.py file, and i can import other modules from my project without any problem... When i am in a diffrent folder than my procekt and i run ipython, a such import have no problem...
from someothermodule.submodule imprort blahblahblah
But, when it comes to importing utils, it fails...
UPATE 2: What caused the problem was the utils directory under django folder, which is also in the python path...
See the PEP on absolute and relative imports for the semantics. You probably want
from .utils.custom_modules import some_function
if you're in a file at the top level of your package.
Edit: This can only be done from inside a package. This is for a good reason -- if you're importing something that is part of your project, then you're already treating it like a Python package, and you should actually make it one. You do this by adding an __init__.py file to project directory.
Edit 2: You've completely changed the question. It may be possible to work around the problem, but the correct thing to do is not refer to your packed the same way as a builtin package. You either need to rename utils, or make it a subpackage of another package, so you can refer to it by a non-conflicting name (like from mydjangoapp.utils.custom_modules import some_function).
I'm not going to bother telling you to try and make sure you don't name your own modules after the stdlib modules;
If you want to leave the name like this, you'll have to use something like this in everything that imports your own utils module:
import sys, imp
utils = sys.modules.get('utils')
if not utils: utils = imp.load_module('utils',*imp.find_module('utils/utils'))
However, unless there's a lot of stuff that you'd have to change after renaming it, I'd suggest you rename it.
I'm really new to Python. I'm trying to import a third party module called primes.py. I have placed this module in C:\Python26\Lib (the location where I installed Python). I then have another file which is trying to import this module. The file attempting to import primes is located at C:\Python26.
In my Python file I have the following two lines:
import primes
import sys
When I run this file, I get the following error:
ImportError: No module named primes
Can anyone help me out?
The module needs to be on your PYTHONPATH or in the same directory as the script, app, or module that is trying to import the module.
I'm not a Windows programmer but if you have placed the module in 'C:\Python26\Lib' and your path is set to 'C:\Python26' you need to add '\Python26\Lib' to your PYTHONPATH. I'm not certain on what the syntax would be but it should be something like 'C:\Python26;C:\Python26\Lib'. Assuming everything is the same on Windows, the subdirectories are not searched automatically.
I think a more appropriate place to put the module is to place it in 'site-packages', I don't know how this is accomplished on Windows. On *nix systems there is a script 'setup.py' that comes with the package/module, and uses 'setuptools' to build and install the package/module for you.
you probably should located this under site-packages directory or a private folder instead. Check your sys.path to understand your import paths.
Put primes.py in the lib/site-packages/ directory.
Also: no need to put your own Python files under the installation directory: I'd advise you to put them somewhere else (where it makes sense).