Changed to built-in tuple and added content types

Co-authored-by: Mark McDonald <i@ii.net>

Author: felipetovarhenao

site/en/tutorials/audio/music_generation.ipynb

@@ -1073,7 +1073,7 @@
         "def predict_next_note(\n",
         "    notes: np.ndarray, \n",
         "    keras_model: tf.keras.Model, \n",
-        "    temperature: float = 1.0) -> Tuple:\n",
+        "    temperature: float = 1.0) -> tuple[int, float, float]:\n",
         "  \"\"\"Generates a note as a tuple of (pitch, step, duration), using a trained sequence model.\"\"\"\n",
         "\n",
         "  assert temperature > 0\n",