Hi Reader,

Regardless of whether you enrolled, thanks for sticking with me through the launch of my new course! 🚀

I've already started exploring topics for the next course... 😄

🔗 Link of the week

​git cheat sheet (PDF)

A well-organized and highly readable cheat sheet from Julia Evans, the brilliant mind behind Wizard Zines!

👉 Tip #48: Three ways to set your environment variables in Python

I was playing around with Mistral LLM this weekend (via LangChain in Python), and I needed to set an environment variable in order to provide my API key to Mistral.

There are many common reasons you might need to set an environment variable, but they all center around providing configuration details to an application.

Below, I'll show you three ways to set an environment variable in Python:

Method 1: os.environ

The simplest method is to use Python's built-in os module. os.environ acts like a dictionary, and so this code sets an environment variable with the key MISTRAL_API_KEY and the value NotMyRealKey.

However, this method isn't secure since your API key is now stored within the code.

Method 2: os.environ & getpass

This method uses Python's built-in getpass module. When you run this code, a text field appears so that you can paste in your API key.

The API key will never be shown on screen, which makes it more secure than method #1, but it's less convenient since you need to paste in your key every time you run the code.

Method 3: dotenv

This method uses the python-dotenv library, which you can install using pip or conda. All you have to do is create a text file named .env, and then include the key and value as shown here:

The load_dotenv function reads the key-value pairs from the file and sets them as environment variables.

Assuming you exclude the .env file from your code repository (probably using .gitignore), this is a reasonable method for storing your API key secretly.

👋 See you next week!

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- Kevin

P.S. Your Life in Weeks​

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