code: def test():
      pals = ["", "a", "aa", "aba", "abba"]
      notpals = ["aA", "abA", "abxBa", "abxxBa"]
      test_(is_palindrome, pals, notpals)
      test_(is_palindrome_r, pals, notpals)
      test_(is_palindrome_r2, pals, notpals)
  
label_desc: Use image node_id 5 for calling a global function with example usage: test() without return types