I have a file structure as shown below,
MainFolder
__init__.py
FirstFolder
__init__.py
firstFile.py
SecondFolder
__init__.py
secondFile.py
Inside firstFile.py, I have a class named Math and I want to import this class in secondFile.py.
Code for firstFile.py
class Math(object):
def __init__(self, first_value, second_value):
self.first_value = first_value
self.second_value = second_value
def addition(self):
self.total_add_value = self.first_value + self.second_value
print(self.total_add_value)
def subtraction(self):
self.total_sub_value = self.first_value - self.second_value
print(self.total_sub_value)
Code for secondFile.py
from FirstFolder.firstFile import Math
Math(10, 2).addition()
Math(10, 2).subtraction()
When I tried running secondFile.py I get this error: ModuleNotFoundError: No module named 'First'
I am using Windows and the MainFolder is located in my C drive, under C:\Users\Name\Documents\Python\MainFolder
Possible solutions that I have tried are, creating the empty __init__.py for all main and sub folders, adding the dir of MainFolder into path under System Properties environment variable and using import sys & sys.path.append('\Users\Name\Documents\Python\MainFolder').
Unfortunately, all these solutions that I have found are not working. If anyone can highlight my mistakes to me or suggest other solutions, that would be great. Any help will be greatly appreciated!
There are potentially two issues. The first is with your import statement. The import statement should be
from FirstFolder.firstFile import Math
The second is likely that your PYTHONPATH environment variable doesn't include your MainFolder.
On linux and unix based systems you can do this temporarily on the commandline with
export PYTHONPATH=$PYTHONPATH:/path/to/MainFolder
On windows
set PYTHONPATH="%path%;C:\path\to\MainFolder"
If you want to set it permanently, use setx instead of set
Related
Similar to ImportError: Cannot import name X, I have a main.py file and, in the same folder, a few other python files bill.py and flatmate.py.
bill.py and flatmate.py each contain classes, nothing more.
Directory structure:
parentfolder
- main.py
- bill.py
- flatmate.py
- files
- pic.png
- doc.pdf
Sample code:
main.py:
import bill # won't work
from flatmate import Flatmate # won't work
...
bill.py:
class Bill:
def __init__(self, ...):
...
flatmate.py:
class Flatmate:
def __init__(self, ...):
...
I get an ImportError: cannot import name 'Bill' from 'bill' (c:\Users\lavid\Desktop\Python Experimente\Python OOP Kurs\App-2-Flatmates-Bill\bill.py). I am pretty sure I don't have circular references. What could be the cause of this problem?
Make sure that all files are next each others
try:
from . import module
if this doesn't work , add your files dir to the Question
Saving the referenced files before accessing them helped a lot.
I have following folder structure
|
|---notebook
| |
| --- MyNoteBook.ipnyb
|
|---python
| |
| --- image_rotation_utils.py
I have following content in python.image_rotation_utils.py
class ImageRotationUtils:
""" Utils for rotating images."""
def __init__(self, image_path=None, image_name=None, output_path=None, output_annotations_file=None ):
""" Initializes the class.
Args:
image_path: the relative path to the image
image_name: image file name
output_path: the relative path where rotated output file is stored.
output_annotations_file: annotations file where rotated anotations are stored.
"""
self.image_path = image_path
self.image_name = image_name
self.output_path = output_path
self.output_annotations_file = output_annotations_file
#other functions defined
Now in MyNoteBook.ipnyb I have following cells
Cell 1:
import sys
sys.path.insert(0, '..')
from python.image_rotation_utils import *
Above is executed successfully now in cell 2 I have below
myUtils = ImageRotationUtils()
I have getting below error
----> 1 ImageRotationUtils()
TypeError: __init__() missing 4 required positional arguments: 'image_path', 'image_name', 'output_path', and 'output_annotations_file'
whye I am getting this error when I have default values in constructor has None in class definition.
I am new to python and trying to put code in productive manner. What mistake I am making. Kindly provide inputs
What you pasted looks ok to me, and your code works for me without errors.
Perhaps something before or after that code is what is spoiling the class definition?
Perhaps you are running this in Jupyter or in IPython and you imported ImageRotationUtils previously, but then changed the code, and tried to reimport again -- and something was wrong with the new reimport so your definition did not get over-written? If that's the case, restart the environment (or the kernel in Jupyter) and rerun the code.
I would suggest putting a simple initialization code, like that constructor line, into the same source file and executing it as a separate process to test if that is the code or the environment issue.
As a matter of convenience and to avoid tweaking sys.path in your code, I would suggest adding your python directory to the PYTHONPATH environment variable before you load your environment, so you can just import.
I have the following file structure
home/user/app.py
home/user/content/resource.py
home/user/content/call1.py
home/user/content/call2.py
I have imported resources.py in app.py as below:
import content.resource
Also, I have imported call1 and call2 in resource.py
import call1
import call2
The requirement is to run two tests individually.
run app.py
run resource.py
When I run app.py, it says cannot find call1 and call2.
When run resource.py, the file is running without any issues. How to run app.py python file to call import functions in resource.py and also call1.py and call2.py files?
All the 4 files having __init__ main function.
In your __init__ files, just create a list like this for each init, so for your user __init__: __all__ = ["app", "content"]
And for your content __init__: __all__ = ["resource", "call1", "call2"]
First try: export PYTHONPATH=/home/user<-- Make sure this is the correct absolute path.
If that doesn't solve the issue, try adding content to the path as well.
try: export PYTHONPATH=/home/user/:/home/user/content/
This should definitely work.
You will then import like so:
import user.app
import user.content.resource
NOTE
Whatever you want to use, you must import in every file. Don't bother importing in __init__. Just mention whatever modules that __init__ includes by doing __all__ = []
You have to import call1 and call2 in app.py if you want to call them there.
How do I load a python module, that is not built in. I'm trying to create a plugin system for a small project im working on. How do I load those "plugins" into python? And, instaed of calling "import module", use a string to reference the module.
Have a look at importlib
Option 1: Import an arbitrary file in an arbiatrary path
Assume there's a module at /path/to/my/custom/module.py containing the following contents:
# /path/to/my/custom/module.py
test_var = 'hello'
def test_func():
print(test_var)
We can import this module using the following code:
import importlib.machinery
myfile = '/path/to/my/custom/module.py'
sfl = importlib.machinery.SourceFileLoader('mymod', myfile)
mymod = sfl.load_module()
The module is imported and assigned to the variable mymod. We can then access the module's contents as:
mymod.test_var
# prints 'hello' to the console
mymod.test_func()
# also prints 'hello' to the console
Option 2: Import a module from a package
Use importlib.import_module
For example, if you want to import settings from a settings.py file in your application root folder, you could use
_settings = importlib.import_module('settings')
The popular task queue package Celery uses this a lot, rather than giving you code examples here, please check out their git repository
I found a solution to add files in library.zip via: Extend py2exe to copy files to the zipfile where pkg_resources can load them.
I can access to my file when library.zip is not include the exe.
I add a file : text.txt in directory: foo/media in library.zip.
And I use this code:
import pkg_resources
import zipfile
from cStringIO import StringIO
my_data = pkg_resources.resource_string(__name__,"library.zip")
filezip = StringIO(my_data)
zip = zipfile.ZipFile(filezip)
data = zip.read("foo/media/text.txt")
I try to use pkg_resources but I think that I don't understand something because I could open directly "library.zip".
My question is how can I do this when library.zip is embed in exe?
Best Regards
Jean-Michel
I cobbled together a reasonably neat solution to this, but it doesn't use pkg_resources.
I need to distribute productivity tools as standalone EXEs, that is, all bundled into the one .exe file. I also need to send out notifications when these tools are used, which I do via the Logging API, using file-based configuration. I emded the logging.cfg fileto make it harder to effectively switch-off these notifications i.e. by deleting the loose file... which would probably break the app anyway.
So the following is the interesting bits from my setup.py:
LOGGING_CFG = open('main/resources/logging.cfg').read()
setup(
name='productivity-tool',
...
# py2exe extras
console=[{'script': productivity_tool.__file__.replace('.pyc', '.py'),
'other_resources': [(u'LOGGINGCFG', 1, LOGGING_CFG)]}],
zipfile=None,
options={'py2exe': {'bundle_files': 1, 'dll_excludes': ['w9xpopen.exe']}},
)
Then in the startup code for productivity_tool.py:
from win32api import LoadResource
from StringIO import StringIO
from logging.config import fileConfig
...
if __name__ == '__main__':
if is_exe():
logging_cfg = StringIO(LoadResource(0, u'LOGGINGCFG', 1))
else:
logging_cfg = 'main/resources/logging.cfg'
fileConfig(logging_cfg)
...
Works a treat!!!
Thank you but I found the solution
my_data = pkg_resources.resource_stream("__main__",sys.executable) # get lib.zip file
zip = zipfile.ZipFile(my_data)
data = zip.read("foo/media/doc.pdf") # get my data on lib.zip
file = open(output_name, 'wb')
file.write(data) # write it on a file
file.close()
Best Regards
You shouldn't be using pkg_resources to retrieve the library.zip file. You should use it to retrieve the added resource.
Suppose you have the following project structure:
setup.py
foo/
__init__.py
bar.py
media/
image.jpg
You would use resource_string (or, preferably, resource_stream) to access image.jpg:
img = pkg_resources.resource_string(__name__, 'media/image.jpg')
That should "just work". At least it did when I bundled my media files in the EXE. (Sorry, I've since left the company where I was using py2exe, so don't have a working example to draw on.)
You could also try using pkg_resources.resource_filename(), but I don't think that works under py2exe.