docstr: Applies Focal Loss: https://arxiv.org/pdf/1708.02002.pdf
docstr_tok: ["Applies","Focal","Loss",":","https",":","\/\/arxiv.org\/pdf\/1708.02002.pdf"]
code: def __init__(
      self,
      gamma: float = 2.0,  # Focusing parameter. Higher values down-weight easy examples' contribution to loss
      weight: Tensor = None,  # Manual rescaling weight given to each class
      reduction: str = "mean",  # PyTorch reduction to apply to the output
  ):
      "Applies Focal Loss: https://arxiv.org/pdf/1708.02002.pdf"
      store_attr()
  
imports: from __future__ import annotations
  from .imports import *
  from .torch_imports import *
  from .torch_core import *
  from .layers import *
label_desc: Use image node_id 1 to create a new FocalLoss object from inherited base classes: Module with example: obj = FocalLoss(gamma, weight, reduction)