code: def build_loss(config, epsilon=None):
      class_dim = config["class_dim"]
      loss_func = Loss(class_dim=class_dim, epsilon=epsilon)
      return loss_func
  
imports: import paddle
  import paddle.nn.functional
label_desc: Use image node_id 1 for calling a global function with example usage: build_loss(config, epsilon) and returns: loss_func