Access environment variables in Python (2024)

FAQs

How can I access environment variables in Python? ›

One way to access environment variables is to use os. environ like a dictionary. For example, os. environ['SHELL'] will contain the value of the SHELL environment variable.

In your Python code, import the dotenv module, and use load_dotenv() to load variables from the . env file. Access the values using os. getenv(“KEY”) for each key-value pair defined in the .

The os. getenv() method returns the value of the environment variable key, if it exists. Note: This method is available for both Unix and Windows.

On Windows

Select Start > All Programs > Accessories > Command Prompt. In the command window that opens, enter set. A list of all the environment variables that are set is displayed in the command window.

Python-dotenv's Command-Line Interface

You can replace /path/to/your/. env with the path to your . env file, VARIABLE_NAME with the name of the variable you want to print or delete, and NEW_VARIABLE and "New Value" with the name and value of the variable you want to set.

To display the values of environment variables, use the printenv command. If you specify the Name parameter, the system only prints the value associated with the variable you requested.

To see a list of the Python virtual environments that you have created, you can use the 'conda env list' command. This command will give you the names as well as the filesystem paths for the location of your virtual environments.

How to add Python path to environment variables? ›

In Bash, you can check if an environment variable is set using the '-z' or '-n' test operators, with the syntax -z "${VAR}" or -n "${VAR}" . These operators help you determine whether a variable is unset or if it's set to some string. In this example, we've set the variable VAR to 'Hello, World!

The .getenv( ) function is the best method to retrieve existing variables. Since it is a dictionary, you can use brackets notation (not recommended) or the .get() function to retrieve a value.

Select Start select Control Panel. double click System and select the Advanced tab. Click Environment Variables. In the section System Variables find the PATH environment variable and select it.

To use the virtual environment you created to run Python scripts, simply invoke Python from the command line in the context where you activated it. For instance, to run a script, just run python myscript.py .

To permanently modify the default environment variables, click Start and search for 'edit environment variables', or open System properties, Advanced system settings and click the Environment Variables button. In this dialog, you can add or modify User and System variables.