func (db *InMemoryDB) GetHeadBlock(transaction ...interface{}) (*chainhash.Hash, error) {
	db.lock.Lock()
	defer db.lock.Unlock()
	return &db.head, nil
}
// GetHeadBlock gets the head block.
GetHeadBlock gets the head block.
// GetHeadBlock gets the head block .
func (db *InMemoryDB) GetHeadBlock(transaction ...interface{}) (*chainhash.Hash, error) {
	db.lock.Lock()
	defer db.lock.Unlock()
	return &db.head, nil
}
func ( db * InMemoryDB ) GetHeadBlock ( transaction ... interface { } ) ( * chainhash . Hash , error ) { db . lock . Lock ( ) defer db . lock . Unlock ( ) return & db . head , nil }
GetHeadBlock gets the head block.
GetHeadBlock gets the head block .