code: public static IGeneratorSet asGeneratorSet( JsonObject json)
      {
      GeneratorSet generatorSet = new GeneratorSet();
  
      // Get generator definitions
      json.keySet().stream()
        .forEach( function -> {
          try
            {
            generatorSet.addGenerator( validFunction( function), asGenerator( json.getJsonObject( function)));
            }
          catch( GeneratorSetException e)
            {
            throw new GeneratorSetException( String.format( "Error defining generator for function=%s", function), e);
            }
          });
  
      return generatorSet;
      }
docs: Returns the IGeneratorSet represented by the given JSON object.