code: public byte[] generateImageForHELMMolecule(String notation)
  			throws BuilderMoleculeException, CTKException, IOException, ValidationException, ChemistryException {
  		byte[] result = Images.generateImageHELMMolecule(validate(notation));
  		setMonomerFactoryToDefault(notation);
  		return result;
  	}
docs: method to generate a HELM molecule
  
  @param notation
  HELM string
  @return generated molecule image in byte[]
  @throws ValidationException
  if the HELM string is not valid
  @throws BuilderMoleculeException
  if the molecule can't be built
  @throws CTKException
  general ChemToolKit exception passed to HELMToolKit
  @throws IOException
  if the image can not be produced
  @throws ChemistryException
  if the Chemistry Engine can not be initialized