I was having trouble with circular dependencies, only to find some advice online that I'm better off importing an entire module rather than specific items within a module. Prior to the circular dependency issue, I was having no issue with imports.
So with the blog's advice, I setup a __init__.py in a folder containing a few models, imported each there, and now when I try to import from that module, I'm being told that module doesn't have an attribute I'm looking for.
So I have this file structure:
└── root
├── models
│ ├── __init__.py
│ ├── a.py
│ └── b.py
└── c.py
In __init__.py, I have
from models.a import A
from models.b import B
And in c.py
import models
# code
models.A.func()
But I get the error module 'models' has no attribute 'A'. As A and B both reference each other, I was getting circular imports at first, but now that they're resolved, I can't get the models to show up at all.
You either need to add your project's directory to PYTHONPATH or you need to do
from . import models
your __init__.py file doesn't require any change. I think in c.py file, type as follows :
modele_name.function_name()
If u have imported that function in your __init__.py file, this will help you, I suppose.
For more details, please edit your question and add the git link of your repo
Related
I am trying to import a util package one directory up from where my code is, but I get an ImportError which I don't understand.
I have a number of different variations on the import syntax in Python, none of which are working.
There are a number of similar questions on Stack Overflow, but none have helped me understand or fix this issue.
Of the top of my head, I have tried the following variations:
import util
import ..util
from .. import util
from ..util import parser
from AdventOfCode2022 import util
from ..AdventOfCode2022 import util
from ...AdventOfCode2022 import util
Most of these I guessed wouldn't work, but I tried them anyway to be sure.
Error message:
ImportError: attempted relative import with no known parent package
Directory structure:
.
├── day03
│ ├── input.txt
│ ├── part1.py
│ ├── part2.py
│ └── test_input.txt
└── util
├── __init__.py
└── parser.py
I just want to import my util package from any "day0*/" directory - not sure why Python makes it so hard!
Two options:
Add the full path to ./util/ to your PYTHONPATH environment variable.
For example on Bash, your ~/.bashrc might have export PYTHONPATH="${PYTHONPATH}:/Users/foobar/projects/advent-of-code/util/".
Add sys.path.append('/path/to/application/app/folder') before the import.
The other solutions don't work because:
day03 and the parent directory are not modules with their own __init__.py. Lines like from ..util import parser only work if everything involved is a module.
You are presumably running the code from within ./day03/.
View this as 'I have a bunch of independent Python projects (day01, day02 etc) that all want to share a common piece of code I have living in a different project (util) that lives somewhere else on my computer.'
I'm working on a python 3.8.5 project which has this folder structure:
project/
├── __init__.py
|── foo.py
|── bar.py
├── utils/
│ ├── __init__py
│ └── configurator.py
└── server/
├── __init__.py
├── models.py
In server/models.py I need to use a class Configurator declared inside utils/configurator.py:
# server/models.py
from utils.configurator import Configurator
# some code here ...
Unfortunately I get this error: ModuleNotFoundError: No module named 'utils'. I dont't understand how it cannot find the utils module since I've properly set the init.py file inside that folder.
I've also tried with relative import:
# server/models.py
from ..utils.configurator import Configurator
# some code here ...
this time getting the following error: ImportError: attempted relative import with no known parent package
Finally, I've attempted with an absolute import, with no results again:
# server/models.py
from projects.utils.configurator import Configurator
# some code here ...
The error this time is: ModuleNotFoundError: No module named 'projects'
Based on this previous question it seems correct to me, I can't understand what I'm messing with.
My code editor is Visual Studio Code and when I type from utils. ... it gives the right suggestion, although I don't think this piece of information could be of any utility.
I have a beeware project and also want to use my own modules in it like Models and Controllers. Also, a module which creates some objects I can test with.
But when I want to import the module to create the test objects and use the method it just throws an error:
ImportError: attempted relative import beyond top-level package
After some research, I know that the path (directory) structures, where I put my modules in, and where the package is, are important. But where ever I put the modules it has the same (or kinda like this) errors. But I can import my Models to create objects of these classes. I also can't decide where the start point of the briefcase is.
Here my structure currently:
/Project_Dir (own created)
/briefcase_project (created from briefcase)
/src
/Models (own created)
/app_directory (created from briefcase)
here is the __main__.py and the __init__.py (the start point I guess) and the app.py (where beeware code is, and also my module import from Test)
/Test (own created, here is a file with a method I want to call)
Sadly there is not so much stuff to find about beeware so I could find a solution.
Please help. Thanks ^^
I did the following to workaround the issue. The example using the Beeware Tutorial 2 source code is on Github
.
├── __init__.py
├── __main__.py
├── app.py
├── mylib <--- # my lib.
│ ├── __init__.py
│ └── testlib.py
└── resources
├── __init__.py
├── beewarecustomlibexample.icns
├── beewarecustomlibexample.ico
└── beewarecustomlibexample.png
2 directories, 9 files
The mylib/testlib.py
def test(text: str) -> str:
return f"Hello: {text}"
In the app.py:
import toga
from toga.style import Pack
from toga.style.pack import COLUMN, ROW
from beewarecustomlibexample.mylib.testlib import test # Import custom lib
class BeewareCustomLibExample(toga.App):
def startup(self):
...
def say_hello(self, widget):
# Calling my test method
result = test(self.name_input.value)
self.main_window.info_dialog("Test Dialog", result)
def main():
return BeewareCustomLibExample()
The above is how I got it working. I've built it on MacOS and works fine.
Take your project folder name and then import from there, so if you're tinkering with the tutorial and you've set up a module folder called myModule in the same directory as your app.py and you have a file called file.py with a class called myClass, you might type:
from helloworld.myModule.file import myClass
I've got a PyCharm "project" in Python, which is to say that I have a folder that is a conglomeration of all sorts of experimental python files, convenience methods/classes, and Jupyter notebooks from following along with online classes.
I've actually just written something that I'm proud of and would like to re-use. I'm finding it difficult to import. I have looked at and attempted implementing the answers to the following questions to no avail:
Can't import my own modules in Python
How to import my own modules in python 3.6?
How to import my own modules the elegant way?
Project structure:
learning_project
|
├───.idea
│ ├───dictionaries
│ └───inspectionProfiles
|
├───decision_trees
├───linear_algebra
├───neural_networks
| ├───based_sequential.py <---------------------------- # Module location #
│ ├───cross-entropy-gradient-descent
│ └───learning pytorch
| ├─── class_notebook.ipynb <---------------------- # Want to import for use here #
| └───Cat_Dog_data
|
└───venv
├───Include
├───Lib
│ └───site-packages
└───Scripts
I have tried the following:
import based_sequential
from based_sequential import ClassName
import based_sequential.ClassName
import neural_networks
from neural_networks import based_sequential
import neural_networks.based_sequential
from neural_networks.based_sequential import ClassName
All result in the error No module named '<pick your poison>'
Question 1: Obviously, what am I missing?
Question 2: Is my organization here part of the problem? I'm starting to suspect that it is.
I also suspect I have some work to do learning the administrative aspects of writing code that is bigger than just one .py file.
I hope you're returning some value in the function/module you're trying to import. If not, check that.
Otherwise, just use sys.path from sys module and direct it towards the file you want to import.
>>> import sys
>>> sys.path
['',
'C:\\Python33\\Lib\\idlelib',
'C:\\Windows\\system32\\python33.zip',
'C:\\Python33\\DLLs',
'C:\\Python33\\lib',
'C:\\Python33',
'C:\\Python33\\lib\\site-packages']
I suggest you check on relative imports.
https://realpython.com/absolute-vs-relative-python-imports/
The way you can solve this problem is shown below:
FILE STRUCTURE I'LL BE USING:
└── project
├── package1
│ ├── module1.py
│ └── module2.py
└── package2
├── __init__.py
├── module3.py
├── module4.py
└── subpackage1
└── module5.py
To import from module 2 while in module 1 use:
from .module2 import function1
In the case of importing the module3 from module2 use:
from ..package2 import module3
IN YOUR OWN CASE, IT SHOULD BE:
from ..based_sequential import whatever
I have a question regarding one single module that is distributed over multiple directories.
Let's say I have these two file and directories:
~/lib/python
xxx
__init__.py
util
__init__.py
module1.py
module2.py
~/graphics/python
xxx
__init__.py
misc
__init__.py
module3.py
module4.py
So then in my Python modules, I did this:
import sys
pythonlibpath = '~/lib/python'
if pythonlibpath not in sys.path: sys.path.append(pythonlibpath)
import xxx.util.module1
which works.
Now, the problem is that I need xxx.misc.module3, so I did this:
import sys
graphicslibpath = '~/graphics/python'
if graphicslibpath not in sys.path: sys.path.append(graphicslibpath)
import xxx.misc.module3
but I get this error:
ImportError: No module named misc.module3
It seems like it somehow still remembers that there was a xxx package in ~/lib/python and then tries to find misc.module3 from there.
How do I get around this issue?
You can't without an extreme amount of trickery that pulls one package structure into the other. Python requires that all modules in a package be under a single subdirectory. See the os source to learn how it handles os.path.
Python does indeed remember that there was a xxx package. This is pretty much necessary to achieve acceptable performance, once modules and packages are loaded they are cached. You can see which modules are loaded by looking the the dictionary sys.modules.
sys.modules is a normal dictionary so you can remove a package from it to force it to be reloaded like below:
import sys
print sys.modules
import xml
print sys.modules
del sys.modules['xml']
print sys.modules
Notice that after importing the xml package it is the dictionary, however it is possible to remove it from that dictionary too. This is a point I make for pedagogical purposes only, I would not recommend this approach in a real application. Also if you need to use your misc and util packages together this would not work so great. If at all possible rearrange your source code structure to better fit the normal Python module loading mechanism.
This is addressed by Implicit Namespace Packages in Python 3.3. See PEP-420.
This is an adaptation of an answer to a similar question.
Following up on #Gary's answer, the PEP 420 page says to use the following code on shared __init__.py packages.
__init__.py:
from pkgutil import extend_path
__path__ = extend_path(__path__, __name__)
This code should be placed inside the xxx directory's __init__.py.
See the *s below
someroot/
├── graphics
│ └── python
│ └── xxx
│ ├── ****__init__.py****
│ └── misc
│ ├── __init__.py
│ ├── module3.py
│ └── module4.py
└── lib
└── python
└── xxx
├── ****__init__.py****
└── util
├── __init__.py
├── module1.py
└── module2.py
Some setup.sh file to add to the Python Path:
libPath=someroot/lib/python/
graphicsPath=someroot/graphics/python/
export PYTHONPATH=$PYTHONPATH:$libPath:$graphicsPath
Python test code (tested on Python versions 2.7.14 and 3.6.4 using pyenv):
import xxx.util.module1
import xxx.misc.module3 # No errors