presto-teradata-functions/src/main/java/io/prestosql/teradata/functions/TeradataFunctionsPlugin.java/TeradataFunctionsPlugin/getFunctions
class TeradataFunctionsPlugin:    @Override
    public Set<Class<?>> getFunctions()
    {
        return ImmutableSet.<Class<?>>builder()
                .add(TeradataDateFunctions.class)
                .add(TeradataStringFunctions.class)
                .build();
    }