create or replace function hello(name text)

    returns text

as $$

#    str = name+',你吃饭了吗?';

#    return 'hello %s !' % str;

    return 'Hello %s!' % name

$$ language plpythonu;

create or replace function hello_invoker(name text)

    returns text

as $$

begin

    return public.hello('[plpgsql_invoker_prefix]' || name);

end;

$$ language plpgsql;

create or replace function hello_invoker_wrap(name text)

    returns text

as $$

    pyret = plpy.execute("select hello_invoker('" + name + "[python wrap suffix]') as ret")[];

    return pyret['ret'];

$$ language plpythonu;