What is the use of "threshold_list" in the Lepton_get_object_temp example?

The example shows

Color Tracking Thresholds (Grayscale Min, Grayscale Max)

threshold_list = [(200, 255)]

What does this do? Does changing this value change the output temperature? should not the output temperature be irrelevant of input?
I am using a lepton 2.5.

Dear friend.
The camera takes all the temp values and map them to greyscale image. (0-255 values)
0 stands for black (min temp) and 255 for white (max temp)
so if min temp is 20 degrees and max temp is 40 degrees , 128 greyscale value will be the 30 degrees.
Then threshold list is used for blob detection just to track the temp you want.

thats wonderful. thank you very much. Can you also tell me how can I extract these grayscale value from an image per pixel.

Dear friend in the example you are working is everything.
In addition the program has a script that calculates all these grayscale values of the blob found and exports the estimated temperature in celcius!