New to Python and getting errors when importing modules. I have the following structure (not sure if this is a good way to show folder structure):
ecommerce
customer
__init__.py
contact.py
shopping
__init__.py
sales.py
__init__.py
I want to import contact.py from customer into sales.py in shopping but get presented with: ModuleNotFoundError: No module named 'eccommerce'.
I'm using this:
from ecommerce.customer import contact at start of the sales.py file.
Any ideas?
VSCode, MacOS 10.14.6
One thing to pay attention to is where is your current working directory located. If you have the cwd set to be in ecommerce than you should be able to access the contact with the syntax you inputted.
I ran into this issue several times and in the python documentation this setup should technically work, init files being parsed by the python parser as individual packages which you can then access. It seems though that it won't work with the standard python interpreter and I haven't found the answer why. One way to get around this is to do as #Sory suggests, at the beginning of your package entry, add the path to the environment variable. This is a work around though and can lead to problems later on.
Another option is to use a separate python interpreter, i use for example the IPython interpreter from Jupyter which runs with this setup perfectly fine. This will give you another external dependency though.
Be sure though that the current working directory is set to be the root folder though as that is usually the first problem.
from ecommerce.customer import contact would work if 'customer' was a class in the ecommerce.py file, but in your case, those are different files so it doesn't work...
The correct syntax would be:
from customer import contact
but you need to adjust those files.
Another way around would be to import os, navigate to that ecommerce folder like so: os.getcwd('insert dir path here'), and then import customer.
Related
I am creating a tool I plan to put on Github. It is very general however I want to also include some examples of its usage. As such I have set up the following folder structure.
This tool is for python 3.
repository/
commonTool.py
commonTool2.py
specificUsage/
runTheSpecificUsage.py
helpRunTheSpecificUsage.py
Now both of the scripts in the specificUsage/ folder will import the methods in commonTool.py and commonTool2.py.
My issue is ideally the user would be able to go
python repository/specificUsage/runTheSpecificUsage.py
However I cant get this to work. It never is able to import the functions that are in the folder above it. I have tried a variety of various posts on how to import a file from a super folder with no luck.
How should I be setting up these folders? Should I have one init.py or two? Where?
You can create a setup.py at the top level along with commonTool.py and commonTool2.py. Inside your setup.py, put the following line:
import setuptools
setuptools.setup(packages=setuptools.find_packages())
Then put an __init__.py in the same level, as well as in specificUsage/. You should be able to import from specificUsage like this:
import commonTool
After setting up your files, from the top level run:
pip install -e .
You may also want to consider that Python has strong naming conventions for modules and packages and frowns upon camelcase in general. You can read more here if you like.
I recently was asked to deliver a python project as part of an interview process.
I tested my project on Windows and MacOSX, with Pycharm, Spyder, jupyter notebook and command line and everything works fine.
However, the reviewer was unable to make the project work on his side, because of module import issues according to him.
My modules are organized like this:
my_project/
my_module.py
main_module.py
my_package/
__init__.py
my_submodule_1.py
my_submodule_2.py
my_submodule_1.py:
import my_module
import my_submodule_2
I haven't added any path related to this project in PYTHONPATH.
The project main function is located in main_module.py.
The reviewer seem to have problems with the modules imported in my_submodule_1.py.
Could anyone shed some light on possible mistakes here and why it would work on my side and not on his?
Your my_submodule_1 module is doing an implicit relative import when it imports my_submodule_2 directly.
That's not legal in Python 3. It is allowed in Python 2, though its usually a bad idea to use it. You can get the Python 3 semantics by putting from __future__ import absolute_import above the other import statements in your file. To fix the import, you'd want to change import my_submodule_2 to either import my_package.my_submodule_2 (an absolute import) or from . import my_submodule2 (an explicit relative import).
If your interviewer is using Python 3 and you're using Python 2, there are likely to be other issues with your code (especially if you're doing any sort of text processing), so I'd make sure you're testing your code in the version they expect!
I think since my_module.py is not in same directory as my_submodule1.py ,and on the reviewer pc the sys.path doesn't have that location of my_module.py, that's why it getting problem in importing the module from its parent directory.
if u give the details of error that the reviewer is getting it might help finding the right solution.
I used below solution for importing dependencies.
I found this solution works if I run the code in Pycharm but not in Terminal.
The error message in Terminal is "cannot find graphics.primitive".
I'm using Mac and Python 3.5.
Why I see different behaviors from the Terminal and Pycharm?
How may I make the solution work for both?
http://chimera.labs.oreilly.com/books/1230000000393/ch10.html#_solution_169
Making a Hierarchical Package of Modules
Problem
You want to organize your code into a package consisting of a hierarchical collection of modules.
Solution
Making a package structure is simple. Just organize your code as you wish on the file-system and make sure that every directory defines an init.py file. For example:
graphics/
__init__.py
primitive/
__init__.py
line.py
fill.py
text.py
formats/
__init__.py
png.py
jpg.py
Once you have done this, you should be able to perform various import statements, such as the following:
import graphics.primitive.line
from graphics.primitive import line
import graphics.formats.jpg as jpg
You need to make sure that the graphics package is in the Python search path. PyCharm does this by extending sys.path as follows:
import sys
sys.path.extend(['/Users/hackworth/Development/graphics_parent_dir', '/Applications/PyCharm.app/Contents/helpers/pycharm', '/Applications/PyCharm.app/Contents/helpers/pydev'])
You can do the same in your code replacing /Users/hackworth/graphics_parent_dir with the appropriate path, or you can include the full path to graphics_parent_dir in the PYTHONPATH environment variable. See the Python documentation for details.
Another option would be to place the graphics package into a location the is searched by default on your system.
I'm self-taught in the Python world, so some of the structural conventions are still a little hazy to me. However, I've been getting very close to what I want to accomplish, but just ran into a larger problem.
Basically, I have a directory structure like this, which will sit outside of the normal python installation (this is to be distributed to people who should not have to know what a python installation is, but will have the one that comes standard with ArcGIS):
top_directory/
ArcToolbox.tbx
scripts/
ArcGIStool.py (script for the tool in the .tbx)
pythonmod/
__init__.py
general.py
xlrd/ (copied from my own python installation)
xlwt/ (copied from my own python installation)
xlutils/ (copied from my own python installation)
So, I like this directory structure, because all of the ArcGIStool.py scripts call functions within the pythonmod package (like those within general.py), and all of the general.py functions can call xlrd and xlwt functions with simple "import xlrd" statements. This means that if the user desired, he/she could just move the pythonmod folder to the python site-packages folder, and everything would run fine, even if xlrd/xlwt/xlutils are already installed.
THE PROBLEM:
Everything is great, until I try to use xlutils in general.py. Specifically, I need to "from xlutils.copy import copy". However, this sets off a cascade of import errors. One is that xlutils/copy.py uses "from xlutils.filter import process,XLRDReader,XLWTWriter". I solved this by modifying xlutils/copy.py like this:
try:
from xlutils.filter import process,XLRDReader,XLWTWriter
except ImportError:
from filter import process,XLRDReader,XLWTWriter
I thought this would work fine for other situations, but there are modules in the xlutils package that need to import xlrd. I tried following this advice, but when I use
try:
import xlrd
except ImportError:
import os, sys, imp
path = os.path.dirname(os.path.dirname(sys.argv[0]))
xlrd = imp.load_source("pythonmod.xlrd",os.path.join(path,"xlrd","__init__.py"))
I get a new import error: In xlrd/init.py, the info module is called (from xlrd/info.py), BUT when I use the above code, I get an error saying that the name "info" is not defined.
This leads me to believe that I don't really know what is going on, because I thought that when the init.py file was imported it would run just like normal and look within its containing folder for info.py. This does not seem to be the case, unfortunately.
Thanks for your interest, and any help would be greatly appreciated.
p.s. I don't want to have to modify the path variables, as I have no idea who will be using this toolset, and permissions are likely to be an issue, etc.
I realized I was using imp.load_source incorrectly. The correct syntax for what I wanted to do should have been:
imp.load_source("xlrd",os.path.join(path,"xlrd","__init__.py"))
In the end though, I ended up rewriting my code to not need xlutils at all, because I continued to have import errors that were causing many more problems than were worth dealing with.
I am experimenting with python, mostly troubleshooting other people's code. I am trying to get a program to run, "path\folderA\program.py".
I am running the program from path\folderA
I am getting an error:
ImportError: No module named fff.ggg.ppp
program.py contains an import:
from fff.ggg.ppp import mmm
In the folder "path\folderB" there are:
"path\folderB\fff\__init__.py"
"path\folderB\fff\ggg"
folder ggg also contains __init__.py, as well as program ppp.py
From reading other posts, like Python error "ImportError: No module named" I understand that having the __init__.py makes a folder a "package" which makes imports from it possible - but it doesn't work, since I am getting an error.
This has been working for other people that worked with these projects, so there is something wrong with my setup.
I read something about the directories having to be in the sys.path. Does that mean I have to add them to the environment variable path ? That would mean adding a lot of directories to the PATH though, so it can't be.
So I also found the following:
import sys
sys.path.append( <path to FolderB> )
But that means changing the code (which has not been necessary for other people) and hard-coding a path to what it is on my local machine - which I shouldn't have to, right ?
I can't visualize it - apparently I am not supposed to change the code and hard-code the physical path to the import module - so how can a program from folderA even know to look in folderB for an import ?
How does the magic of __init__.py work ?
I can't visualize it - apparently I am not supposed to change the code
and hard-code the physical path to the import module - so how can a
program from folderA even know to look in folderB for an import ?
You are correct. Somehow you have to tell python to look for imported modules in folderB. There is no __init__.py magic that lets you import from other folders on your hard drive.
Usually, if you've got various different python packages like that, they work by being installed into python's library. That way they can imported from anywhere. This is usually accomplished by a setup.py script. Check if folderB has one. Run it with python setup.py install.
If that doesn't work, we'll need more information about how this code is structured.
Folder B must be on the sys.path, so you would either need to move mmm to A, or modify sys.path from within A (not sure if that works). __init__.py tells python that the folder is a package, so you could have folders with __init__.py within folders with __init__.py and python treats the folders inside as parts of the parent folder. Check out sympy or almost any large python library and you will find such a structure. It can also contain code to be run on import, but can also be empty.