code: def set_data_processor(
      self, preprocess_fn: Callable, postprocess_fn: Callable
  ) -> DataProcessor:
      data_preprocessor = self.set_default_processor()
      if preprocess_fn:
          data_preprocessor.set_preprocess_fn(preprocess_fn)
      if postprocess_fn:
          data_preprocessor.set_postprocess_fn(postprocess_fn)
      return data_preprocessor
  
file_path: chitra/chitra/serve/base.py
imports: import itertools
  from typing import Callable, List, Optional
  from chitra.data_processing import DataProcessor
  from chitra.serve import constants
label_desc: Use image node_id 3 for calling the ModelServer obj's underlying member method code with example usage: obj.set_data_processor(preprocess_fn, postprocess_fn) and returns: data_preprocessor