code: def log_model(self, is_best, prefix, metadata=None):
      pass
  
file_path: PaddleOCR/ppocr/utils/loggers/vdl_logger.py
imports: from .base_logger import BaseLogger
  from visualdl import LogWriter
label_desc: Use image node_id 3 for calling the VDLLogger obj's underlying member method code with example usage: obj.log_model(is_best, prefix, metadata) without return types