code: def is_packet_trace(path):
      
      path = os.path.abspath(path)
      if not os.path.isfile(path):
          return False
  
      try:
          f = open(path, 'rb')
      except:
          return False
  
      magic = f.read(4)
      f.close()
  
      return magic in FILE_TYPE_HANDLER
docs: Determine if a file is a packet trace that is supported by this module.
  
      Args:
          path (str): path to the trace file.
  
      Returns:
          bool: True if the file is a valid packet trace.