code: def save_encoded_video_manifest(
      encoded_video_infos: Dict[str, EncodedVideoInfo],
      file_name: str = None,
  ) -> str:
      """
      Saves the encoded video dictionary as a csv file that can be read for future usage.
  
      Args:
          video_frames (Dict[str, EncodedVideoInfo]):
              Dictionary mapping video_ids to metadata about the location of
              their video data.
  
          file_name (str):
              location to save file (will be automatically generated if None).
  
      Returns:
          string of the filename where the video info is stored.
      """
      file_name = (
          f"{os.getcwd()}/encoded_video_manifest.csv"
          if file_name is None
          else file_name
      )
      save_dataclass_objs_to_headered_csv(
          list(encoded_video_infos.values()), file_name
      )
      return file_name
  
imports: import datetime
  import os
  from dataclasses import dataclass
  from enum import Enum
  from typing import Dict, Optional, Union
  from pytorchvideo.data.encoded_video import EncodedVideo
  from pytorchvideo.data.frame_video import FrameVideo
  from pytorchvideo.data.utils import DataclassFieldCaster, load_dataclass_dict_from_csv, save_dataclass_objs_to_headered_csv
  from pytorchvideo.data.video import Video
label_desc: Use image node_id 2 for calling a global function with example usage: save_encoded_video_manifest(encoded_video_infos, file_name) and returns: file_name