code: def test_lengths_arg_exists():
      from speechbrain.utils.callchains import lengths_arg_exists
  
      def non_len_func(x):
          return x + 1
  
      def len_func(x, lengths):
          return x + lengths
  
      assert not lengths_arg_exists(non_len_func)
      assert lengths_arg_exists(len_func)
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_lengths_arg_exists() and returns: unknown, unknown