title: It is possible to change loss in Tensorflow object detection api?
body: <p>i want to change loss of object detection for ones of object detection (such as SSD) ,</p>
  
  <p>Q1 : i want to know where do i modify the loss function for SSD ,</p>
  
  <p>Q2 : is it possible to fine-tune ssd_mobilenet on my dataset with my define loss ? is it good or must be train ssd_mobile from scratch with my loss function ?</p>