code: def _map_encoding(encoding: str) -> str:
      for dst in ["PCM_S", "PCM_U", "PCM_F"]:
          if dst in encoding:
              return dst
      if encoding == "PCM_MULAW":
          return "ULAW"
      elif encoding == "PCM_ALAW":
          return "ALAW"
      return encoding
  
imports: import os
  import re
  import sys
  from typing import BinaryIO, Optional, Tuple, Union
  import torch
  import torchaudio
  from .backend import Backend
  from .common import AudioMetaData
label_desc: Use image node_id 11 for calling a global function with example usage: _map_encoding(encoding) and returns: encoding, str, dst, str