code: def __init__(self, max_epochs: int, data_dir: str):
      super().__init__()
      self.data_dir = data_dir
      # Init an image classifier with resnet18 backbone
      self.train_work_1 = ImageClassifierTrainWork(
          max_epochs,
          "resnet18",
      )
      # Init an image classifier with resnet26 backbone
      self.train_work_2 = ImageClassifierTrainWork(
          max_epochs,
          "resnet26",
      )
      # Init the serving component
      self.server_work = ImageClassifierServeWork()
  
file_path: pytorch-lightning/docs/source-app/code_samples/quickstart/app/app_1.py
imports: import flash
  from flash.core.data.utils import download_data
  from flash.image import ImageClassificationData, ImageClassifier
  from lightning.app import LightningWork, LightningFlow, LightningApp, CloudCompute
  from lightning.pytorch.callbacks import ModelCheckpoint
label_desc: Use image node_id 1 to create a new RootFlow object from inherited base classes: LightningFlow with example: obj = RootFlow(max_epochs, data_dir)