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+# cloudprog-hw4
+Team 02
+
+## Features
+- `lambda-gen-s3-url.py`: AWS Lambda function that generates S3 presigned URL for IoT thing to upload.
+  - Envs:
+    - `MQTT_TOPIC`: `S3_URL_TOPIC`
+    - `BUCKET`: S3 bucket to upload
+- `lambda-detect-face.py`: AWS Lambda function that calls rekognition API tiggered by S3 events.
+  - Envs:
+    - `MQTT_TOPIC`: `LED_TOPIC`
+- `led_control.py`: Code run on IoT thing.
+  - Controls the LED with MQTT topic.
+  - Take picture and upload it to S3.
+    - Send upload request via MQTT topic `S3_UPLOAD_TOPIC`
+    - Get presigned URL via `S3_URL_TOPIC`
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