code: public List<Monomer> getAllMonomersList() {
      List<Monomer> monomers = new ArrayList<Monomer>();
      for (String polymerType : getPolymerTypeSet()) {
        Map<String, Monomer> map = getMonomers(polymerType);
        monomers.addAll(map.values());
      }
      return monomers;
  
    }
docs: This method returns all monomers of the store as list sorted by polymer
  type
  
  @return all monomers of store as {@code List<{@link Monomer}>}