Update README.md

Author: twitchard

Diff for: tts/tts-python-quickstart/README.md

@@ -31,6 +31,17 @@ See the [Quickstart guide](https://dev.hume.ai/docs/text-to-speech-tts/quickstar
     uv add hume python-dotenv aiofiles
     ```
 
+    Optional: For audio playback functionality, install PyAudio:
+    
+    First, install the required system dependencies:
+    - macOS: `brew install portaudio`
+    - Linux: `sudo apt-get install python3-dev libasound2-dev portaudio19-dev`
+    
+    Then install the Python package:
+    ```shell
+    uv sync --extra playback
+    ```
+
 3. Set up your API key:
 
     You must authenticate to use the Hume TTS API. Your API key can be retrieved from the [Hume AI platform](https://platform.hume.ai/settings/keys). For detailed instructions, see our documentation on [getting your api keys](https://dev.hume.ai/docs/introduction/api-key).

Diff for: tts/tts-python-quickstart/pyproject.toml

@@ -9,3 +9,8 @@ dependencies = [
   "hume>=0.7.11",
   "python-dotenv>=1.0.1",
 ]
+
+[project.optional-dependencies]
+playback = [
+  "pyaudio>=0.2.13",
+]