code: public static List<AtomSite> convertChainToAtomSites(Chain c, int model, String chainName, String chainId) {
  
  		List<AtomSite> list = new ArrayList<>();
  
  		if (c.getEntityInfo()==null) {
  			logger.warn("No entity found for chain {}: entity_id will be set to 0, label_seq_id will be the same as auth_seq_id", c.getName());
  		}
  
  		for ( int h=0; h<c.getAtomLength();h++){
  
  			Group g= c.getAtomGroup(h);
  
  			list.addAll(convertGroupToAtomSites(g, model, chainName, chainId));
  
  		}
  
  		return list;
  	}
docs: Converts a Chain into a List of {@link AtomSite} objects
  @param c the chain
  @param model the model number for the output AtomSites
  @param chainName the chain identifier (author id) for the output AtomSites
  @param chainId the internal chain identifier (asym id) for the output AtomSites
  @return