Function understanding (part 2)

[OneManArmy93]

Hello, can anyone explain what is the utility of this function create_objectness_label and what does it do in the train process.
Also, in the train_test() function in model_01_deconv I couldn't find the declation of the cordinate function and What does it do?
And last question, why is there 3 loss function and what is the utility of each one?
Thank you