code: def Decode(self, encoded_data):
      
      try:
        # TODO: replace by libuna implementation or equivalent. The behavior of
        # base64.b64decode() does not raise TypeError for certain invalid base64
        # data e.g. b'\x01\x02\x03\x04\x05\x06\x07\x08' these are silently
        # ignored.
        decoded_data = base64.b64decode(encoded_data)
      except (TypeError, binascii.Error) as exception:
        raise errors.BackEndError(
            'Unable to decode base64 stream with error: {0!s}.'.format(
                exception))
  
      return decoded_data, b''
docs: Decode the encoded data.
  
      Args:
        encoded_data (byte): encoded data.
  
      Returns:
        tuple(bytes, bytes): decoded data and remaining encoded data.
  
      Raises:
        BackEndError: if the base64 stream cannot be decoded.