Error Importing a variable from one Python script to another - python

I have two Python (3.8) scripts located in the same folder.
The first lookup.py is simply:
#! /usr/bin/env python3
import os
from getimp import session0
print (session0)
The second script getimp.py identifies a cookie and sets it as a variable which is imported into the first script. I have omitted some of the code here, but hopefully have the critical parts.
#! /usr/bin/env python3
import os
import json
import base64
import sqlite3
import shutil
from datetime import datetime, timedelta
import win32crypt # pip install pypiwin32
from Crypto.Cipher import AES # pip install pycryptodome
def get_chrome_datetime(chromedate):
"""Return a `datetime.datetime` object from a chrome format datetime
....
....
# you can also search by domain, e.g thepythoncode.com
cursor.execute("""
SELECT host_key, name, value, creation_utc, last_access_utc, expires_utc, encrypted_value
FROM cookies
WHERE name like '%user_id%'""")
# get the AES key
key = get_encryption_key()
for host_key, name, value, creation_utc, last_access_utc, expires_utc, encrypted_value in cursor.fetchall():
if not value:
decrypted_value = decrypt_data(encrypted_value, key)
else:
# already decrypted
decrypted_value = value
print(f"""
{decrypted_value}
===============================================================""")
session0 = decrypted_value
if __name__ == "__main__":
main()
If I run getimp.py on its own it generates the correct result but when I run lookup.py I get an error:
File "lookup", line 4, in <module>
from getimp import session0
ImportError: cannot import name 'session0' from 'getimp' (D:\Documents\ptest\getimp.py)
Am I losing the variable once the script getimp.py finishes?

Your problem is that the variablesession0 is defined inside the scope of get_chrome_datetime and therefore can not be addressed from import.
Try importing the function and create the variable inside the scope of the active script.
Inside 'get_chrome_datetime' change session0=decrypted_value into return decrypted_value
and in lookup.py :
import os
from getimp import get_chrome_datetime
print (get_chrome_datetime(argument))

Your problem is that session0 is defined inside the function.
I would suggest the following
session0 = None
def get_chrome_datetime(chromedate):
global session0
... (your code here)
Also you should call the function outside of if __name__ == '__main__' because when you're importing a module, the __name__ wouldn't be "__main__"

Related

ModuleNotFoundError: I can't import custom modules properly

below the folder structure of my software:
below the code of all the .py files:
run.py:
import modules.module_01.aa as a
a.test()
# test:
if __name__=="__main__":
pass
aa.py (module 1):
import libraries.qq as q
import libraries.zz as z
def test():
q.qq_fun()
z.zz_fun()
print("ciao")
qq.py (library used by aa.py):
def qq_fun():
pass
zz.py (library used by aa.py):
def zz_fun():
pass
my question is really simple, why when I run "run.py" Python say to me:
why "aa.py" can't import the module "qq.py" and "zz.py"? how can I fix this issue?
run.py
In run.py, the Python interpreter thinks you're trying to import module_01.aa from a module named module. To import aa.py, you'll need to add this code to the top of your file, which adds the directory aa.py is in to the system path, and change your import statement to import aa as a.
import sys
sys.path.insert(0, "./modules/module_01/")
aa.py
The same problem occurs in aa.py. To fix the problem in this file, you'll need to add this code to the top of aa.py, which adds the directory qq.py and zz.py are in, and remove the libraries. from both of your import statements.
import sys
sys.path.insert(0, "./modules/module_01/libraries")

Call another installed package in Python

I'm new to Python. What I want to do is after setup esptool package (pip install esptool) call its main method with a bunch of arguments in my application. Something like:
esptool.py -p /dev/ttyUSB0 write_flash -fm qio 0x0000
There is an issue I faced. esptool is not on the packages list in python to import (it is installed with pip already). How am I gonna user import and call the main method?
Resolving import issues
You can't simply invoke import esptool because esptool.py is an executable script, thus not meant to be imported like a plain module. However, there are workarounds for importing code from executable scripts; here are two I know of:
extending sys.path
You can extend the sys.path to include the bindir containing the esptool.py script. Simple check from command line:
$ PYTHONPATH=$(which esptool.py)/.. python -c "import esptool; esptool.main()"
should print you the usage help text.
Extending sys.path in code:
import os
import sys
try:
from shutil import which
except ImportError:
from distutils.spawn import find_executable as which
bindir = os.path.dirname(which('esptool.py'))
sys.path.append(bindir) # after this line, esptool becomes importable
import esptool
if __name__ == '__main__':
esptool.main()
using import machinery
You can avoid extending sys.path by using the mechanisms of importing Python code from arbitrary files. I like this solution more than fiddling with sys.path, but unfortunately, it is not portable between Python 2 and 3.
Python 3.5+
import importlib.machinery
import importlib.util
from shutil import which
if __name__ == '__main__':
loader = importlib.machinery.SourceFileLoader('esptool', which('esptool.py'))
spec = importlib.util.spec_from_loader(loader.name, loader)
esptool = importlib.util.module_from_spec(spec)
loader.exec_module(esptool) # after this line, esptool is imported
esptool.main()
Python 2.7
import imp
from distutils.spawn import find_executable as which
if __name__ == '__main__':
esptool = imp.load_source('esptool', which('esptool.py'))
esptool.main()
Passing command line arguments
The command line arguments are stored in sys.argv list, so you will have to temporarily overwrite it in order to pass the arguments to the main function:
# assuming esptool is imported
import sys
if __name__ == '__main__':
# save the current arguments
argv_original = sys.argv[:]
# overwrite arguments to be passed to esptool argparser
sys.argv[:] = ['', '-p', '/dev/ttyUSB0', 'write_flash', '-fm', 'qio', '0x0000']
try:
esptool.main()
except Exception:
# TODO deal with errors here
pass
finally: # restore original arguments
sys.argv[:] = argv_original

Python import class from other files

I have three files under the same directory, namely, main.py, Newtester.py, and fileUtility.py. In Newtester.py there is a class named Function. In main.py, there are the following codes:
from file.py import *
...
def main():
...
funcs = parseFuncSpec(funcInputFile)
parseFuncSpec is defined in fileUtilities.py as:
some code to import Newtester.py
def parseFuncSpec(fName):
curFunc = function(funcName, numTest, [], score)
Regardless of what I put in import Newtester.py, I always get an error saying "Function" (the class defined in the file "Newtester.py") is not defined. Following Python: How to import other Python files, I have attempted
import Newtester
__import__("Newtester")
exec("Newtester.py")
exec("Newtester")
import importlib
importlib.__import__("Newtester")
os.system("Newtester.py")
But none of them seemed to work. Any advice is appreciated. See https://github.com/r2dong/unitTesting if you are interested in seeing the complete files.
It's because you are not using it correctly
well when you use import statement like below only Newstester file is imported
import Newtester
hence instead of using parseFuncSpec() directly you have to use it as Newtester.parseFuncSpec()
or to use parseFuncSpec() directly you need to use below import statement:
from Newtester import parseFuncSpec

Module undefined after importing it in a function

I'm trying to use a function called start to set up my enviroment in python. The function imports os.
After I run the function and do the following
os.listdir(simdir+"main")
I get a error that says os not defined
code
>>> def setup ():
import os.path
import shutil
simdir="e:\\"
maindir="c:\\backup\\bitcois\\test exit\\"
>>> setup()
>>> os.listdir(simdir+"main")
Traceback (most recent call last):
File "<pyshell#10>", line 1, in <module>
os.listdir(simdir+"main")
NameError: name 'os' is not defined
The import statement is scoped. When importing modules they are defined for the local namespace.
From the documentation:
Import statements are executed in two steps: (1) find a module, and initialize it if necessary; (2) define a name or names in the local namespace (of the scope where the import statement occurs). [...]
So in your case the os package is only defined within function setup.
You are getting this error because you are NOT importing the whole os library but just the os.path module. In this way, the other resources at the os library are not made available for your use.
In order to be able to use the os.listdir method, you need to either import it alongside the os.path like this:
>>> def setup ():
import os.path, os.listdir
import shutil
simdir="e:\\"
maindir="c:\\backup\\bitcois\\test exit\\"
or import the full library:
>>> def setup ():
import os
import shutil
simdir="e:\\"
maindir="c:\\backup\\bitcois\\test exit\\"
You can read more here:
https://docs.python.org/2/tutorial/modules.html
try:
import os.path
import shutil
import glob
def setup ():
global simdir
simdir="e:\\"
maindir="c:\\backup\\bitcois\\test exit\\"
setup()
os.listdir(simdir+"main")
You need to return the paths and assign the returned values in the global scope. Also, import os too:
import os
def setup():
# retain existing code
return simdir, maindir
simdir, maindir = setup()
When you import os or do any sort of command within a function, the command's effect only last while that function itself is running. What you need to do is
import os
...Do your function and other code
This way, your import lasts for the whole program :).

Import custom modules on IPython.parallel engines with sync_imports()

I've been playing around with IPython.parallel and I wanted to use some custom modules of my own, but haven't been able to do it as explained on the cookbook using dview.sync_imports(). The only thing that has worked for me was something like
def my_parallel_func(args):
import sys
sys.path.append('/path/to/my/module')
import my_module
#and all the rest
and then in the main just to
if __name__=='__main__':
#set up dview...
dview.map( my_parallel_func, my_args )
The correct way to do this would in my opinion be something like
with dview.sync_imports():
import sys
sys.path.append('/path/to/my/module')
import my_module
but this throws an error saying there is no module named my_module.
So, what is the right way of doing it using dview.sync_imports()??
The problem is that you're changing the PYTHONPATH just in the local process running the Client, and not in the remote processes running in the ipcluster.
You can observe this behaviour if you run the next piece of code:
from IPython.parallel import Client
rc = Client()
dview = rc[:]
with dview.sync_imports():
import sys
sys.path[:] = ['something']
def parallel(x):
import sys
return sys.path
print 'Local: ', sys.path
print 'Remote: ', dview.map_sync(parallel, range(1))
Basically all the modules that you want to use with sync_imports must already be in the PYTHONPATH.
If it's not in the PYTHONPATH then you must add it to the path in the function that you execute remotely, and then import the module in the function.

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