Set up your machine

This page sets up everything you need before Session 1. Finish it once and every session in the course will work. The stack is deliberately tiny: Python 3.10+, a virtual environment, and a .env file with your API keys.

Step 1 — Check your Python version

You need Python 3.10 or newer (3.12+ recommended for Session 6). Verify yours:

If it prints 3.10 or higher, you are good. Otherwise install Python from python.org or via Homebrew (`brew install python@3.12`).

Step 2 — Clone the course material

Grab the course folder your instructor shared with you (Session1, Session5, Session6, etc.). Open a terminal and `cd` into it:

Step 3 — Create a virtual environment

Each session folder has its own requirements. Create a venv inside the session folder you are starting with. Example for Session 1:

Step 4 — Install dependencies

This installs openai, python-dotenv, and any other libraries the session needs. Repeat this step once per session folder.

Step 5 — Create your .env file

Copy the example and open it in your editor:

Paste your OpenAI API key (and, for Session 6, your Anthropic and Google keys). The file should look like this:

OPENAI_API_KEY=sk-...your-key-here...
# Session 6 only
ANTHROPIC_API_KEY=sk-ant-...
GOOGLE_API_KEY=AIza...

# Optional overrides
OPENAI_MODEL=gpt-4o-mini
ANTHROPIC_MODEL=claude-sonnet-4-5
GEMINI_MODEL=gemini-2.0-flash

See "Get Your API Keys" in the sidebar if you do not have keys yet.

Step 6 — Verify your setup

Run this tiny Python snippet to confirm the key is loaded and the API reachable:

from dotenv import load_dotenv
import os
from openai import OpenAI

load_dotenv()
assert os.getenv("OPENAI_API_KEY"), "OPENAI_API_KEY not set"

client = OpenAI()
resp = client.responses.create(
    model="gpt-4o-mini",
    input="Say 'setup working' in 3 words.",
)
print(resp.output_text)