I'm having ImportError: cannot import name 'Literal' from 'typing' error message when I try to use pip install. Anyone can help?
The problem is with the configuration of your environmental variables. The first thing, I'd suggest you do is uninstall all the unused versions of python. To my mind, the latest of python 3.x.x series is the best.
Steps:
The easiest way of accessing it is just to type environment variable in Windows 10 search bar. (Assuming you are using Windows 10)
Then follow these:
At the bottom half part of the subsequent window search for path:
If you double click that, look for python. Make sure you have such paths added there and you need to have a compatible version of python. Usually, your python bin directory is located in Program Files.
Related
I am new to Python and writing a lambda function.
I installed urllib3 using pip but still getting this following error.
I tried restarting vscode/ uninstall and reinstall but still getting the error.
this is the result when I run pip show urllib3
what am i missing here?
You need to make sure that VS Code uses the same Python Interpreter that you installed this package to.
You can see it here:
Looks like yours should point to
c:\user\###\appdata\local\programs\python\python39\bin\python
(or something like that, where your python executable file is located)
Maybe there is more than one python environment on your machine, And the location where you installed the package is inconsistent with the python interpreter you are using now.
You can use CTRL + SHIFT + P to open the command palette and search Python: Select Interpreter (or click on the interpreter version displayed in the lower right corner).
Select the environment interpreter where you have the urllib3 package installed.
Here is the error
import numpy
Exception has occurred: ModuleNotFoundError
No module named 'numpy'
File "C:\path\to\file\32.py", line 1, in <module>
import numpy
Let me know how did you install the NumPy package; using pip or something else?
If you have multiple python versions, i.e. 2.x and 3.x at the same time, please make sure your interpreter for the 32.py file is the version that you installed NumPy on.
To possibly fix your problem, you should first try installing it and see if there are any errors. You should also check the version of Python you are running on Windows 10, because when you update Python it sometimes switches names between py and python
As you can see, the version of Python has changed between py and python so you should try changing that first.
If this does not work, you should try finding the directory for NumPy and adding it to the system PATH in your script. The installer usually shows you the location by doing the following:
import sys
sys.path.append("<insert numpy location here>")
import NumPy
This should manually force it into finding the package. If none of this works, please tell us and we should be able to find a different solution.
Happy Coding!
If you're using a code editor like PyCharm, you could install it by clicking on
file then settings then the project interpreter setting and install new module! You can search for the module and install.
Make sure that the python version that you want to use is a Windows Environmental Variable. You can test this by running this line in your command line.
> python --version
If you get some other python version that is not the one that you wish to use you can set the python version you want by finding where exactly your Python folder is located and go into settings and set the path as a new variable (I can leave a tutorial for you). If that is too much of a hassle, the Python installers can set the python that you will install as an environmental variable for you. (You could uninstall and reinstall and make sure that you allow it to make it an environmental variable.
After that you should be able to import whatever external packages you want using pip
for example:
pip install numpy
X in this example represents any module or package you install.
The problem:
I have a problem with a package called 'X'.
In PyCharm I get an error ImportError: No module named 'X'.
My code runs from the terminal without any problem. Any help ?
or
I installed X on python3.4 with pip. In terminal, when I import X, everything is fine, but when I import it in PyCharm, it says: ImportError: No module named 'X'". Any help ?
This is basically everyday question, just with different module or a package instead name instead of X.
And it's not problem in a package or module you install, it's in a PyCharm Project Interpreter you are currently using for your project.
The following answer is usually solution to this specific problem.
SHORTER VERSION:
If you have squiggly line below module you import...
...move on name of module and press Alt+Enter and select Install package X.
This should (probably !!!) install module you thought you installed, but got ImportError.
LONGER:
If you want to use module X:
Go to File -> Settings -> Project:NameOfProject -> Project Interpreter.
The window that opens has some specific regions:
This is a project interpreter PyCharm is currently using. You can change you python environments here also. If you want to add virtual environment you created manually, continue reading.
A little "cog" or a "gear" is used to Add, Edit or Remove environments. If you want to add virtual environment you created manually, select Add... when gear icon is clicked, and make sure to set proper path to python.exeof your virtual environment.
IMPORTANT: A list of all installed packages, represented by: Package name and Version. If you tried to use package, but got ImportError no module named 'X', make sure to check if package is listed here!!!. If not, it's not installed in the current python environment and it should be installed (continue reading).
A little + represents Install. It can be used to install packages. Simply click on + sign, search for a package and click Install Package at the bottom after you found it. You can also specify the version you want of a package. In example below, we searched for flask package.
A package should be installed and listed now in installed packages.
PyCharm creates a virtual environment with its own Python Interpreter for your project, you need to install the module for the interpreter you are using. To do this go to Settings -> Project: yourProjectName -> Python Interpreter, click the plus icon and select the module you would like to install.
Alternatively you could force PyCharm to use your other Interpreter by selecting it from the dropdown at the top of the Python Interpreter settings page I mentioned before.
There are many reasons for this.
The reason and fix I'm going to put here is extremely rare, just decided to put it hoping at least a single person can get help from this answer.
The issue
PyCharm treats __init__.py as a non python file.
This happens when you forgot to use .py extension in your code's __init__.py files, and then you add the extension later. Then pycharm starts treating all __init__.py files (even external library files) as non python. How strange?
Detect if the issue is this
Scroll click on the library name (not the module name).
Or right click and goto Declaration or Usages
You will see the library's __init__.py as plain text.
If you see the code as plain text, that's the issue!
The Solution
Find the file location in pycharm navigation. If you are using virtual environment, the file fill be in venv/lib/site-packages/{library_name}.
Right click on __init__.py, click override file type. Select python.
You'll see the error is gone!
I'm running a code on deep learning, which uses the opencv module, by running python main.py (contains import cv2 statement), but always get the error 'ImportError: dynamic module does not define module export function (PyInit_cv2)'.
I've tried to reinstall my anaconda and create new virtual environments, but all got the same result. This problem really confuses me a lot and I've googled for many related problems, none of them works. I think the problem is something related to the environment and has nothing to do with the code, because I got the same result by simply run import cv2 in python prompt. The more confusing thing is that, even after I remove the opencv module, I also get the same problem, but not a ModuleNotFoundError. Does anyone can give me some advice? Thanks a lot!
I think I found one possible reason of this error.
Recently I was configuring the caffe environment on one server, I downloaded the source code of opencv-2.4.13 and compiled manually, added /usr/local/opencv-2.4.13/build/lib to $PYTHONPATH, and caffe worked well. After that, when I entered one of my virtual environment using conda activate py35, which uses python3.5, tried import cv2 in the python prompt, got the error above.
I'm not sure but I think the cause of the error is opencv-2.4.13 compiles a python2 interface so it can't be imported by python3. Python imports packages by searching the directories listed in sys.path, where $PYTHONPATH is in the second place after the current working directory (This is a great article introduces the mechanism of python finding packages). So when we enter the py35 environment, python will first look for $PYTHONPATH and find the opencv installed on the root directory instead of finding the opencv in the virtual environment using conda install opencv-python.
So there are two solutions of this problem:
Use python2 instead.
Remove /usr/local/opencv-2.4.13/build/lib from $PYTHONPATH.
which all work for me.
Similar post, might help:
ImportError: dynamic module does not define init function (initfizzbuzz)
Could you provide info on how you installed the CV module?
I had the same problem, which was caused by the cv2.so file in /usr/local/lib/python2.7/site-packages/cv2.so. After I deleted the file and use command sudo pip3 install opencv-python, it worked for python3.
I'm just starting out with Python, and have found out that I can import various libraries. How do I find out what libraries exist on my Mac that I can import? How do I find out what functions they include?
I seem to remember using some web server type thing to browse through local help files, but I may have imagined that!
From the Python REPL (the command-line interpreter / Read-Eval-Print-Loop), type help("modules") to see a list of all your available libs.
Then to see functions within a module, do help("posix"), for example. If you haven't imported the library yet, you have to put quotes around the library's name.
For the web server, you can run the pydoc module that is included in the python distribution as a script:
python /path/to/pydoc.py -p 1234
where 1234 is the port you want the server to run at. You can then visit http://localhost:1234/ and browse the documentation.
Every standard python distribution has these libraries, which cover most of what you will need in a project.
In case you need to find out if a library exists at runtime, you do it like this
try:
import ObscureModule
except ImportError:
print "you need to install ObscureModule"
sys.exit(1) # or something like that
You can install another library: yolk.
yolk is a python package manager and will show you everything you have added via pypi. But it will also show you site-packages added through whatever local package manager you run.
just run the Python interpeter and type the command
import "lib_name"
if it gives an error, you don't have the lib installed...else you are good to go
On Leopard, depending on the python package you're using and the version number, the modules can be found in /Library/Python:
/Library/Python/2.5/site-packages
or in /Library/Frameworks
/Library/Frameworks/Python.framework/Versions/Current/lib/python2.6/site-packages
(it could also be 3.0 or whatever version)...
I guess it is quite the same with Tiger
Considering that in every operating system most of python's packages are installed using 'pip' (see pip documentation) you can also use the command 'pip freeze' on a terminal to print a list of all the packages you have installed through it.
Other tools like 'homebrew' for macOS (used when for some reason you can't install a package using pip) have similar commands, in this specific case 'brew list'.