code: def __init__(self, classes_num=80, image_size=(608, 608)):
      self.classes_num = classes_num
      self.image_size = (image_size[0], image_size[1], 3)
  
      input = tf.keras.Input(shape=self.image_size)
      output = self.CSPDarknet53WithSPP()(input)
      output = self.YOLOHead()(output)
      super().__init__(input, output)
  
      self.loss_tracker = tf.keras.metrics.Mean(name="loss")
      self.lr_tracker = tf.keras.metrics.Mean(name="lr")
      self.mAP_tracker = tf.keras.metrics.Mean(name="mAP")
  
imports: import tensorflow
  import numpy
  from layers import Mish, ScaledRandomUniform
  import utils
label_desc: Use image node_id 1 to create a new YOLOv4Model object from inherited base classes: tf.keras with example: obj = YOLOv4Model(classes_num, image_size)