Datasheet

Try covering with your hand or shining a lamp onto the sensor to experiment with the light
levels!
Library Reference
The Adafruit_TSL2591 library contains a number of public functions to help you get
started with this sensor.
Constructor
To create an instance of the Adafruit_TSL2591 driver, simple declare an appropriate object,
along with a 32-bit numeric value to identify this sensor (in case you have several TSL2591s
and want to track them separately in a logging system).
Adafruit_TSL2591 tsl = Adafruit_TSL2591(2591);
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