# Implement a simple traffic light state machine using a dictionary

Canonical URL: <https://datadriven.io/problems/implement-a-simple-traffic-light-state-machine-using-a-dicti-30cabf8a>

Domain: Python · Difficulty: medium

## Problem

Implement a simple traffic light state machine using a dictionary. Start at 'green', transition through 'yellow' to 'red' to 'green' using a 'timer' event. Run 4 transitions and print each state.

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