code: def _wav(h, f):
      # 'RIFF' <len> 'WAVE' 'fmt ' <len>
      if (
          not h.startswith(b"RIFF")
          or h[8:12] != b"WAVE"
          or h[12:16] != b"fmt "
      ):
          return None
      else:
          return "x-wav"
  
file_path: catboost/contrib/tools/python3/src/Lib/email/mime/audio.py
imports: from io import BytesIO
  from email import encoders
  from email.mime.nonmultipart import MIMENonMultipart
label_desc: Use image node_id 5 for calling a global function with example usage: _wav(h, f) and returns: None, str