code: def on_train_batch_begin(
      self, batch: int, logs: Optional[Dict]
  ) -> None:
      print(f"{train_batch_begin}:{batch}:{logs}", file=self.log)
  
imports: import io
  from typing import Any, Callable, Dict, List, Optional, Set
  import determined
  import determined.keras
label_desc: Use image node_id 8 for calling the CBChecker obj's underlying member method code with example usage: obj.on_train_batch_begin(batch, logs) without return types