A34b returns error "region is not defined"

[fractalm83]

Hello, the script on checkpoint A34b of Forest Degradation and Deforestation is retunring the error "region is not define". Would you be able to fix it? Thank you very much

[krishnakafle]

Hi,
The region is supposed to be user-selected by a polygon in GUI. You can also define the fire-affected region as a polygon feature.
For details, follow:
https://google-earth-engine.com/Terrestrial-Applications-part-1/Active-fire-monitoring/
`
// Define a region to calculate histogram for.
var region = ee.Geometry.Rectangle([-112.60, 40.60, -111.18, 41.22]); // Sample polygon, you need to change it

`