Python windows set python path

This question needs a proper answer:

Just use the standard package site, which was made for this job!

and here is how (plagiating my own answer to my own question on the very same topic):

1. Open a Python prompt and type

>>> import site
>>> site.USER_SITE
'C:\\Users\\ojdo\\AppData\\Roaming\\Python\\Python37\\site-packages'
...

(Alternatively, call python -m site --user-site for the same effect.)

1. Create this folder if it does not exist yet:

...
>>> import os
>>> os.makedirs(site.USER_SITE)
...

(Or, in Bash, your preferred variant of makedirs -p $(python -m site --user-site).)

1. Create a file sitecustomize.py (with exactly this filename, or it won’t work) in this folder containing the content of FIND_MY_PACKAGES, either manually or using something like the following code. Of course, you have to change C:\My_Projects to the correct path to your custom import location.

...
>>> FIND_MY_PACKAGES = """
import site
site.addsitedir(r'C:\My_Projects')
"""
>>> filename = os.path.join(site.USER_SITE, 'sitecustomize.py')
>>> with open(filename, 'w') as outfile:
...     print(FIND_MY_PACKAGES, file=outfile)

And the next time you start Python, C:\My_Projects is present in your sys.path, without having to touch system-wide settings. Bonus: the above steps work on Linux, too!

Why does this work?

From the documentation of standard library package site:

[Then] an attempt is made to import a module named sitecustomize, which can perform arbitrary site-specific customizations. […].

So if you create a module named sitecustomize anywhere in PYTHONPATH, package site will execute it at Python startup. And by calling site.addsitedir, the sys.path can be safely extended to your liking.

This question needs a proper answer:

Just use the standard package site, which was made for this job!

and here is how (plagiating my own answer to my own question on the very same topic):

1. Open a Python prompt and type

>>> import site
>>> site.USER_SITE
'C:\\Users\\ojdo\\AppData\\Roaming\\Python\\Python37\\site-packages'
...

(Alternatively, call python -m site --user-site for the same effect.)

1. Create this folder if it does not exist yet:

...
>>> import os
>>> os.makedirs(site.USER_SITE)
...

(Or, in Bash, your preferred variant of makedirs -p $(python -m site --user-site).)

1. Create a file sitecustomize.py (with exactly this filename, or it won’t work) in this folder containing the content of FIND_MY_PACKAGES, either manually or using something like the following code. Of course, you have to change C:\My_Projects to the correct path to your custom import location.

...
>>> FIND_MY_PACKAGES = """
import site
site.addsitedir(r'C:\My_Projects')
"""
>>> filename = os.path.join(site.USER_SITE, 'sitecustomize.py')
>>> with open(filename, 'w') as outfile:
...     print(FIND_MY_PACKAGES, file=outfile)

And the next time you start Python, C:\My_Projects is present in your sys.path, without having to touch system-wide settings. Bonus: the above steps work on Linux, too!

Why does this work?

From the documentation of standard library package site:

[Then] an attempt is made to import a module named sitecustomize, which can perform arbitrary site-specific customizations. […].

So if you create a module named sitecustomize anywhere in PYTHONPATH, package site will execute it at Python startup. And by calling site.addsitedir, the sys.path can be safely extended to your liking.

You may need to add Python to PATH if you’ve installed Python, but typing python on the command line doesn’t seem to work. You may be getting a message saying that the term python isn’t recognized, or you may end up with the wrong version of Python running.

A common fix for these problems is adding Python to the PATH environment variable. In this tutorial, you’ll learn how to add Python to PATH. You’ll also learn about what PATH is and why PATH is vital for programs like the command line to be able to find your Python installation.

The steps that you’ll need to take to add something to PATH will depend significantly on your operating system (OS), so be sure to skip to the relevant section if you’re only interested in this procedure for one OS.

Note that you can use the following steps to add any program to PATH, not just Python.

C:\Users\<USER>\AppData\Local\Programs\Python

# This file is not read by bash(1), if ~/.bash_profile or ~/.bash_login
# exists.

$ echo export PATH="<PATH_TO_PYTHON>:$PATH" >> ~/.profile

>>> PATH = "/home/realpython/apps:/bin"
>>> PATH = f"/home/realpython/python:{PATH}"
>>> PATH
'/home/realpython/python:/home/realpython/apps:/bin'

$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/home/realpython/badpython:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games

$ echo $PATH | tr ":" "\n"
/usr/local/sbin
/usr/local/bin
/usr/sbin
/home/realpython/badpython
/usr/bin
/sbin
/bin
/usr/games
/usr/local/games

export PATH=`echo $PATH | tr ":" "\n" | grep -v 'badpython' | tr "\n" ":"`

If you are a beginner, then this article is for you. As a beginner, you might face problems in setting a proper path for python. In today’s tutorial, we will learn how to set a default path for python whenever we install python into our system.

Introduction

Unlike most operating systems such as Unix, Windows does not include a system-supported installation of Python. To run Python conveniently from a command prompt, you might consider changing some default environment variables in Windows. To temporarily set environment variables, open Command Prompt and use the set command:

C:\>set PATH=C:\Program Files\Python 3.6; %PATH%

Why to set up a path for python?

If you’ve installed Python in Windows using the default installation options, then the path to Python will not be added to the Windows Path variable. The Path variable lists the directories that will be searched for executing when you type a command in the command prompt. By adding the path to the Python executable, you will be able to access python.exe just by typing the python keyword in your command prompt. You will not need to specify the full path to the program.

Let us see what happens if we enter the python command in the command prompt and the path to that executable is not added to the Path variable:

C:\>python 'python' is not recognized as an internal or external command, operable program or batch file.

As you can see from the above output, the command was not found. Therefore, to run python.exe, you will need to specify the full path to the executable.

How to select default path while installing python?

There is an easy way to set up the default path during installing the Python. Every python installer comes with an option to add a python path into environmental variables. This will ensure that you can run python from your terminal. To do this –

1. Get Python Installer from python.org.
2. Get the installer and an installation window will appear.
3. Press the “Add Python X.X to your PATH” option and install the python.

This way you can set up a default path without any headache. If you already have python installed and do not want to reinstall it, then move on to the next methods.

To permanently modify the default environment variables : My Computer > Properties > Advanced System Settings > Environment Variables > Edit

Steps to follow in detail.

• Right-click on ‘My Computer’ or ‘This PC.’ :-To navigate to the Windows Environment Variables screen, where you can add/edit your paths, right-click on the ‘This PC‘ icon. Then, select ‘Properties.’

• Select ‘Properties’ at the bottom of the Context Menu.: – After selecting the properties, the settings pop up.
• Next, select ‘Advanced system settings.’

• Check ‘Environment Variables...’ in the Advanced Tab.: After pressing on the advance settings, another window comes up which shows the Environment Variable option.

• Under ‘System Variables, ‘ Check on the New button in the top half of the dialog to make a new user variable.

• A new user dialog box pop ups which contain Variable name and variable value.

Before you type any values, you’ll need to locate the relevant Python paths. The paths that you’ll need to get are:

• copy the python path as show in the image below

Now let’s fill the New User Variable box that you saw earlier:

For the Variable name, type ‘Path.‘ For the Variable value, copy the full Python application path, then use a semicolon.

Now select OK

Using python from Command Prompt

1. Press on the start menu.
2. Type Command Prompt and open it
3. Type “python.”
   1. A response from the python interpreter comes, i.e., it will show the python version currently installed in your system else.
   2. You will get an error message that will be written as “python is not recognized as an internal or external command.” This means that there is something wrong with the path variable setting.

Checking of python path

1. Press on the start menu.
2. Type Command Prompt and open it
3. Type “python.”
4. Now type the following code.

import os
os.environ['PYTHONPATH']

OUTPUT:- 'C:\Program Files\Python 3.6'

How to handle multiple paths in python?

You may have two versions of python installed in windows in your system, let’s say 2.7 and 3.9. You want to run one of your projects in the python 2.7 version and another project in the 3.9 version. So the problem that lands up here is how you can specify which version you want to use for a specific python project?

So, to check all the versions of python installed in your windows environment , just type

py -0p in command prompt

So, today I will show you 2 methods of how to manage multiple python paths in windows?

Method 1: By defining the path of the versions

Whenever you try to run Python in the command prompt, it searches the %PATH% environment variable and checks for an executable file which can either be a batch file (.bat), command file (.exe), or any other executable file (.exe) that matches the name given. Once the correct file is found, it executes the program using that file. Now, if you have two versions of Python installed on your system (Python 2.7 and 3.9), then the path variable will contain the location of both the directories. But, there is a problem. The problem is once Windows finds the first match, it will stop examining any other path.

To overcome this problem, you have to call one or both applications using their path explicitly. For example, as you can see below, I have two versions of Python installed on my system.

• To execute python 2.7 you must call C:\Python27\python.exe

• To execute python 3.9 we had to type python3.9.exe

This method is one of the simplest method for managing multiple paths of python.

Method 2: Creating a shortcut

If you want to avoid using the entire path, create a shortcut for each python.exe file and rename it as python27 and python39.

In order to create the shortcuts, follow the given steps:

• Navigate to the folder containing the Python version you want to create a shortcut for.

• Right-click and create a shortcut.

• Rename the shortcut.

To run a file in python 2.7

Also, Check Out Editors Choice:

Conclusion

I hope this article helps you in setting a proper path for python in Windows operating system. As a beginner, you might face difficulties, but no worries, keep reading our tutorials on python and being a pro. Drop a comment if you have doubts. We are just one reply away. Till then, keep reading.

Happy Pythoning Geeks!!

There are few ways to add Python to Windows PATH. In this guide, you’ll see two methods to add Python to Windows path:

• Via the installation of a recent version of Python
• Manual entry of the paths

Method 1: Install a Recent Version of Python

You can easily add Python to Windows path by downloading a recent version of Python, and then checking the box to Add Python to PATH at the bottom of the setup screen:

Add Python to PATH

Finish the installation, and you should be good to go.

Alternatively, you may manually add the paths into the Environment variables.

Method 2: Manually add Python to Windows Path

If you wish to stick with the previous version of Python, you may apply the steps below to manually add Python to Windows path.

First, navigate to the Windows Environment Variables screen (where you can add/edit your paths):

• Press the Windows Key + R on your keyboard in order to open the Run dialog box
• Type sysdm.cpl to open the System Properties
• Go to the Advanced tab and then click on the ‘Environment Variables…‘

That should take you to the Environment Variables screen, where you can add/edit your paths.

Under the User variables box, click on ‘New…‘ to add the ‘Path’ variable (note that if your ‘Path’ variable already exists, then click on ‘Edit…’ instead):

You should then see the New User Variable box, where you may add/edit variables:

Variable name:
Variable value:

Before you type any values, you’ll need to locate the relevant Python paths. The paths that you’ll need to get are:

(1) The Python application path, which is the folder where you originally installed Python. You can find the Python application path by following these steps:

• Type “Python” in the Windows Search Bar
• Right-click on the Python App, and then select “Open file location“
• Right-click again on the Python shortcut, and then select “Open file location“

Here is an example of a Python application path:

C:\Users\Ron\AppData\Local\Programs\Python\Python39

(2) The Python Scripts path. The Scripts folder should be located within the Python application path. Example:

C:\Users\Ron\AppData\Local\Programs\Python\Python39\scripts

After you obtained the paths, fill the New User Variable box that you saw earlier:

• For the Variable name, type ‘Path‘
• For the Variable value, paste the full Python application path, then add semicolon (as highlighted in yellow below), and finally paste the Python Scripts path.

For our example:

Variable name: Path
Variable value: C:\Users\Ron\AppData\Local\Programs\Python\Python39;C:\Users\Ron\AppData\Local\Programs\Python\Python39\Scripts

Press ‘OK’ and you would then see your new Python Path under the ‘User variables‘ section. Don’t forget to press ‘OK‘ again so that the changes will get implemented.

You just added Python to the Windows Path.

You should be able to install Python packages easily, by opening the Windows Command Prompt and then typing:

pip install package_name

For example, to install the Pandas package, simply type ‘pip install pandas‘ and then press ENTER:

pip install pandas

Similarly, you may upgrade PIP by typing the following command:

python -m pip install --upgrade pip