code: func (h *BlockHeader) Serialize(w io.Writer) error {
  	// At the current time, there is no difference between the wire encoding
  	// at protocol version 0 and the stable long-term storage format.  As
  	// a result, make use of writeBlockHeader.
  	return writeBlockHeader(w, 0, h)
  }
docs: // Serialize encodes a block header from r into the receiver using a format
  // that is suitable for long-term storage such as a database while respecting
  // the Version field.