class_docstr: Build FGD distill model.
  Args:
      cfg: The student config.
      slim_cfg: The teacher and distill config.
class_docstr_tok: ["Build","FGD","distill","model",".","Args",":","cfg",":","The","student","config",".","slim_cfg",":","The","teacher","and","distill","config","."]
code: def build_loss(self, distill_cfg):
      assert (
          "distill_loss_name" in distill_cfg
          and distill_cfg.distill_loss_name
      )
      assert "distill_loss" in distill_cfg and distill_cfg.distill_loss
      loss_func = dict()
      name_list = distill_cfg.distill_loss_name
      for name in name_list:
          loss_func[name] = create(distill_cfg.distill_loss)
      return loss_func
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import paddle
  import paddle.nn
  from ppdet.core.workspace import register, create, load_config
  from ppdet.utils.checkpoint import load_pretrain_weight
  from ppdet.utils.logger import setup_logger
label_desc: Use image node_id 2 for calling the FGDDistillModel obj's underlying member method code with example usage: obj.build_loss(distill_cfg) and returns: loss_func