code: def serialize_functions(
      data_file_path: str, description: str, functions
  ):
      """Serializes into a file at path `data_file_path` for PyNode functions.
  
      Args:
        data_file_path: The path of the (local) file to write to.
        description: Describes the functions, e,g., the label of the group they
          belongs to. This is propagated to enrich the error message.
        functions: PyNode functions as a list or list-like object.
      """
      enable_lru_cache_pickling_once()
      with open(data_file_path, "wb") as f:
          _cloudpickle_dump_with_user_friendly_error(
              functions, description, f
          )
  
file_path: launchpad/launchpad/launch/serialization.py
imports: import copyreg
  import functools
  from absl import flags
  import cloudpickle
  from launchpad import flags
label_desc: Use image node_id 4 for calling a global function with example usage: serialize_functions(data_file_path, description, functions) without return types