     end
   end
 
-  defmacrop assert_spec({function_name, function_arity}, arguments_spec, return_spec) do
+  defmacrop assert_spec({function_name, function_arity}, arguments_specs, return_spec) do
     quote do
       {:ok, specs} = Code.Typespec.fetch_specs(Form)
 


    @tag task_id: 3
    test "has a typespec" do
      assert_spec({:letters, 1}, "String.t()", "[String.t()]")
    end
  end


    test "has a typespec" do
      assert_spec(
        {:check_length, 2},
        ["word :: String.t(), length :: non_neg_integer()", "String.t(), non_neg_integer()"],
        ":ok | {:error, pos_integer()}"
      )
    end
