code: func (c *Chain) newConfigMetadata(block *common.Block) *etcdraft.ConfigMetadata {
  	metadata, err := ConsensusMetadataFromConfigBlock(block)
  	if err != nil {
  		c.logger.Panicf("error reading consensus metadata: %s", err)
  	}
  	return metadata
  }
docs: // newMetadata extract config metadata from the configuration block