code: private static StringBuilder generateInverse(PolymerNotation polymer) throws HELM2HandledException,
  			RNAUtilsException, org.helm.notation2.exception.NotationException, ChemistryException {
  		initComplementMap();
  		String sequence = getNaturalAnalogSequence(polymer);
  		StringBuilder sb = new StringBuilder(sequence);
  		return sb.reverse();
  	}
docs: method to generate the inverse sequence of the given polymer
  
  @param polymer
  PolymerNotation
  @return inverse sequence of the PolymerNotation
  @throws HELM2HandledException
  if the polymer contains HELM2 features
  @throws RNAUtilsException
  if the polymer is not rna or dna
  @throws org.helm.notation2.exception.NotationException
  @throws ChemistryException
  if the Chemistry Engine can not be initialized