code: def file_chunk_generate(file_path):
      CHUNK_SIZE = 1 * 1024 * 1024
      logging.debug("Splitting model to file chunks")
      with open(file_path, "rb") as f:
          while True:
              piece = f.read(CHUNK_SIZE)
              if not piece:
                  return
              yield ByteChunk(buffer=piece)
  
file_path: BigDL/python/ppml/src/bigdl/ppml/fl/nn/utils.py
imports: import logging
  from bigdl.ppml.utils.safepickle import SafePickle
  import stat
  import numpy
  from bigdl.ppml.fl.nn.generated.nn_service_pb2 import *
  from bigdl.ppml.fl.nn.generated.fl_base_pb2 import FloatTensor, TensorMap
  import numpy
  from bigdl.dllib.utils.log4Error import invalidInputError
  from bigdl.ppml.fl.nn.generated.fl_base_pb2 import FloatTensor, TensorMap
label_desc: Use image node_id 3 for calling a global function with example usage: file_chunk_generate(file_path) without return types