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 Refer to [README](docs/source/index.rst#section-quickstart) for a quickstart of how to use caravel_user_project
 
 Refer to [README](docs/source/index.rst) for this sample project documentation. 
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+In this project, traffic light controller on a four-way road using a sensor is proposed. A sensor on the farm way is to detect if there are any vehicles and change the traffic light to allow the vehicles to cross the highway. Otherwise, highway light is always green since it has higher priority than the farm way.