code: public static String getReverseSequence(PolymerNotation polymer) throws RNAUtilsException, HELM2HandledException,
  			org.helm.notation2.exception.NotationException, ChemistryException {
  		StringBuilder sb = new StringBuilder(getNaturalAnalogSequence(polymer));
  		return sb.reverse().toString();
  	}
docs: method to generate the reverse rna/dna sequence of a given polymer
  
  @param polymer
  PolymerNotation
  @return sequence reverse rna/dna sequence
  @throws RNAUtilsException
  if the polymer is not a RNA/DNA
  @throws HELM2HandledException
  if the polymer contains HELM2 features
  @throws org.helm.notation2.exception.NotationException if notation is not valid
  @throws ChemistryException
  if the Chemistry Engine can not be initialized