Develop Reference

modifying the PYTHONPATH variable in zsh

I would like to add my site-packages directory to the PYTHONPATH variable, so I can import modules which are stored there to use them in scripts in interpreter. My default shell is zsh, and the OS is macOS Monterey, version 12.6.
I have tried to open the ~/.zprofile in nano editor from my terminal, adding the path I need, and restarting my terminal, but it did not help to solve the issue. After restarting the terminal, I tried to run following commands:
narynaa#Narynas-MacBook-Pro ~ % echo ~/.z.profile
/Users/narynaa/.z.profile
narynaa#Narynas-MacBook-Pro ~ % cat ~/.zprofile
# Set PATH, MANPATH, etc., for Homebrew.
eval "$(/opt/homebrew/bin/brew shellenv)"
export PYTHONPATH="/opt/homebrew/lib/python3.10/site-packages"
The path I need is stored inside the ~/.zprofile file now, but the problem is not solved.
Thank you for your help!

Execute a python script as a command

I'm writing a python script which will be placed in a location. I want to execute it just like a command. for ex.
$ find_branch test
where find_branch is a script placed in anywhere in the system.
I would like to know how to achieve this. I can run it on the place where the script is present by chmod u+x on the script and removing the .py from the script

sudo nano /usr/bin/testpyscript
Then inside the script:
#!/usr/bin/python
print("I'm a python script")
Give it x permission:
sudo chmod +x /usr/bin/testpyscript
Now you can use it as a regular command:
bash-4.2$ testpyscript
I'm a python script
It doesn't have to be exactly at /usr/bin, any location that is inside your $PATH will do. Let's say you want it to be located at some folder inside your home directory, you could do something like this:
pwd
/home/brunorb
mkdir somedir
sudo mv /usr/bin/testpyscript somedir/
export PATH=$PATH:/home/brunorb/somedir/
testpyscript # from any folder in the system
I'm a python script

Make sure python has been added to your path and #!/usr/bin/python is located at the top of your script.
Note You could just try adding your script to your /usr/local/bin/ directory and give it the proper permissions.
sudo cp <your script> /usr/local/bin/

You have a number of options on how to achieve this.
Add the location where you put the script to your PATH environment variable, for example in your ~/.bashrc script:
export PATH="${PATH}:/folder/where/you/put/the/script"
Install the script to a location that is already on your path. It does not have to be a system folder like /usr/bin. Many default Bash setups will include ~/bin in your PATH.
Give the full path to your script on the command line:
/folder/where/you/put/the/script/find_branch test
Run the script through Python. This is very similar to option #2:
python /folder/where/you/put/the/script/find_branch test
Create an alias for the script in your environment. In bash you would do something like the following in your ~/.bashrc:
alias find_branch='/folder/where/you/put/the/script/find_branch'
OR
alias find_branch='python /folder/where/you/put/the/script/find_branch'
For options #1, #2, #3 and #5a to work properly, you should have a shebang with the version of python as the first line of the script. Any of the following will do, depending on how you have/want your environment set up:
#!/usr/bin/python
#!/usr/bin/python2
#!/usr/bin/python3
#!/usr/bin/env python
#!/usr/bin/env python2
#!/usr/bin/env python3
Finally, you do not have to remove the .py extension from the script if you do not want to. Many bash scripts have a .sh extension, for example, which does not prevent them from running as-is. You just have to include the extension in the name of the script when you run it.

Where do I find the bashrc file on Mac?

Hello I am following this page.. I'm installing Python onto my mac so that I can set up a Django / Eclipse development environment. However I am not too sure how to go about executing this step:
The script will explain what changes it will make and prompt you
before the installation begins.
Once you’ve installed Homebrew,
insert the Homebrew directory at the top of your PATH environment variable.
You can do this by adding the following line at the bottom of your
~/.bashrc file
export PATH=/usr/local/bin:$PATH
Where do I find the bashrc file on my mac and where do I find the homebrew directory?
I am running a macbook pro with OS 10.8.5.

The .bashrc file is in your home directory.
So from command line do:
cd
ls -a
This will show all the hidden files in your home directory. "cd" will get you home and ls -a will "list all".
In general when you see ~/ the tilda slash refers to your home directory. So ~/.bashrc is your home directory with the .bashrc file.
And the standard path to homebrew is in /usr/local/ so if you:
cd /usr/local
ls | grep -i homebrew
you should see the homebrew directory (/usr/local/homebrew). Source
Yes sometimes you may have to create this file and the typical format of a .bashrc file is:
# .bashrc
# User specific aliases and functions
. .alias
alias ducks='du -cks * | sort -rn | head -15'
# Source global definitions
if [ -f /etc/bashrc ]; then
. /etc/bashrc
fi
PATH=$PATH:/home/username/bin:/usr/local/homebrew
export PATH
If you create your own .bashrc file make sure that the following line is in your ~/.bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi

I would think you should add it to ~/.bash_profile instead of .bashrc, (creating .bash_profile if it doesn't exist.) Then you don't have to add the extra step of checking for ~/.bashrc in your .bash_profile
Are you comfortable working and editing in a terminal? Just in case, ~/ means your home directory, so if you open a new terminal window that is where you will be "located". And the dot at the front makes the file invisible to normal ls command, unless you put -a or specify the file name.
Check this answer for more detail.

On your Terminal:
Type cd ~/ to go to your home folder.
Type touch .bash_profile to create your new file.
Edit .bash_profile with your code editor (or you can just type
open -e .bash_profile to open it in TextEdit).
Type . .bash_profile to reload .bash_profile and update any
functions you add.

In my macOS Monterey version, zsh is the default terminal shell. zsh executes ~/.zshrc every time the terminal is opened.
vi ~/.zshrc
#Add your path export to .zshrc
PATH=/usr/local/bin:$PATH
Now, when you open the terminal, the path will be set correctly.

On some system, instead of the .bashrc file, you can edit your profils' specific by editing:
sudo nano /etc/profile

~/.bashrc is already a path to .bashrc.
If you do echo ~ you'll see that it's a path to your home directory.
Homebrew directory is /usr/local/bin. Homebrew is installed inside it and everything installed by homebrew will be installed there.
For example, if you do brew install python Homebrew will put Python binary in /usr/local/bin.
Finally, to add Homebrew directory to your path you can run echo "export PATH=/usr/local/lib:$PATH" >> ~/.bashrc. It will create .bashrc file if it doesn't exist and then append the needed line to the end.
You can check the result by running tail ~/.bashrc.

The .bash_profile for macOS is found in the $HOME directory. You can create the file if it does not exit. Sublime Text 3 can help.
If you follow the instruction from OS X Command Line - Sublime Text to launch ST3 with subl then you can just do this
$ subl ~/.bash_profile
An easier method is to use open
$ open ~/.bash_profile -a "Sublime Text"
Use Command + Shift + . in Finder to view hidden files in your home directory.

Open Terminal and execute commands given below.
cd /etc
subl bashrc
subl denotes Sublime editor. You can replace subl with vi to open bashrc file in default editor. This will workout only if you have bashrc file, created earlier.

Shell : workon not found [duplicate]

So, once again, I make a nice python program which makes my life ever the more easier and saves a lot of time. Ofcourse, this involves a virtualenv, made with the mkvirtualenv function of virtualenvwrapper. The project has a requirements.txt file with a few required libraries (requests too :D) and the program won't run without these libraries.
I am trying to add a bin/run-app executable shell script which would be in my path (symlink actually). Now, inside this script, I need to switch to the virtualenv before I can run this program. So I put this in
#!/bin/bash
# cd into the project directory
workon "$(cat .venv)"
python main.py
A file .venv contains the virtualenv name. But when I run this script, I get workon: command not found error.
Of course, I have the virtualenvwrapper.sh sourced in my bashrc but it doesn't seem to be available in this shell script.
So, how can I access those virtualenvwrapper functions here? Or am I doing this the wrong way? How do you launch your python tools, each of which has its own virtualenv!?

Just source the virtualenvwrapper.sh script in your script to import the virtualenvwrapper's functions. You should then be able to use the workon function in your script.
And maybe better, you could create a shell script (you could name it venv-run.sh for example) to run any Python script into a given virtualenv, and place it in /usr/bin, /usr/local/bin, or any directory which is in your PATH.
Such a script could look like this:
#!/bin/sh
# if virtualenvwrapper.sh is in your PATH (i.e. installed with pip)
source `which virtualenvwrapper.sh`
#source /path/to/virtualenvwrapper.sh # if it's not in your PATH
workon $1
python $2
deactivate
And could be used simply like venv-run.sh my_virtualenv /path/to/script.py

I can't find the way to trigger the commands of virtualenvwrapper in shell. But this trick can help: assume your env. name is myenv, then put following lines at the beginning of scripts:
ENV=myenv
source $WORKON_HOME/$ENV/bin/activate

This is a super old thread and I had a similar issue. I started digging for a simpler solution out of curiousity.
gnome-terminal --working-directory='/home/exact/path/here' --tab --title="API" -- bash -ci "workon aaapi && python manage.py runserver 8001; exec bash;"
The --workingdirectory forces the tab to open there by default under the hood and the -ci forces it to work like an interactive interface, which gets around the issues with the venvwrapper not functioning as expected.
You can run as many of these in sequence. It will open tabs, give them an alias, and run the script you want.
Personally I dropped an alias into my bashrc to just do this when I type startdev in my terminal.
I like this because its easy, simple to replicate, flexible, and doesn't require any fiddling with variables and whatnot.

It's a known issue. As a workaround, you can make the content of the script a function and place it in either ~/.bashrc or ~/.profile
function run-app() {
workon "$(cat .venv)"
python main.py
}

If your Python script requires a particular virtualenv then put/install it in virtualenv's bin directory. If you need access to that script outside of the environment then you could make a symlink.
main.py from virtualenv's bin:
#!/path/to/virtualenv/bin/python
import yourmodule
if __name__=="__main__":
yourmodule.main()
Symlink in your PATH:
pymain -> /path/to/virtualenv/bin/main.py
In bin/run-app:
#!/bin/sh
# cd into the project directory
pymain arg1 arg2 ...

Apparently, I was doing this the wrong way. Instead of saving the virtualenv's name in the .venv file, I should be putting the virtualenv's directory path.
(cdvirtualenv && pwd) > .venv
and in the bin/run-app, I put
source "$(cat .venv)/bin/activate"
python main.py
And yay!

add these lines to your .bashrc or .bash_profile
export WORKON_HOME=~/Envs
source /usr/local/bin/virtualenvwrapper.sh
and reopen your terminal and try

You can also call the virtualenv's python executable directly. First find the path to the executable:
$ workon myenv
$ which python
/path/to/virtualenv/myenv/bin/python
Then call from your shell script:
#!/bin/bash
/path/to/virtualenv/myenv/bin/python myscript.py

PYTHONPATH is not working for multiple path

I want to set pythonpath, but it doesnt work for other directory.
My bashrc:
export PYTHONPATH=/usr/lib/python2.7
export PYTHONPATH=$PYTHONPATH/plat-linux2:$PYTHONPATH/lib-dynload:$PYTHONPATH/dist-packages:$PYTHONPATH/lib-tk:$PYTHONPATH
If I keep only first line(single directory)
export PYTHONPATH=/usr/lib/python2.7
then, my bash shell takes me to the /usr/lib/python2.7 directory.
But when I include multiple directory -
export PYTHONPATH=$PYTHONPATH/plat-linux2:$PYTHONPATH/lib-dynload:$PYTHONPATH/dist-packages:$PYTHONPATH/lib-tk:$PYTHONPATH
It throws error like
bash: cd: /usr/lib/python2.7/plat-linux2:/usr/lib/python2.7/lib-dynload:/usr/lib/python2.7/dist-packages:/usr/lib/python2.7/lib-tk:/usr/lib/python2.7: No such file or directory

Don't use PYTHONPATH to construct more joined paths. Use some temp variable.
PY_BASE=/usr/lib/python2.7
PYTHONPATH=$PY_BASE:$PY_BASE/plat-linux2:$PY_BASE/lib-dynload
PYTHONPATH=$PYTHONPATH:$PY_BASE/dist-packages:$PY_BASE/lib-tk
export PYTHONPATH
Also, the cd command has nothing to do with the PYTHONPATH. Meaning you are doing something completely unrelated to try and cd into your PYTHONPATH.