Lazy load external libraries when needed

- Improves start-up time
- Prevents immediate failure if the libraries cannot be imported
- Other core functionalities can thus be preserved
- Resolves #17 as an official workaround

pymusiclooper/core.py

@@ -2,13 +2,15 @@
 import shutil
 from typing import Tuple
 
-import soundfile
-import taglib
+import lazy_loader as lazy
 
 from .analysis import find_best_loop_points
 from .audio import MLAudio
 from .playback import PlaybackHandler
 
+# Lazy-load external libraries when they're needed
+soundfile = lazy.load("soundfile")
+taglib = lazy.load("taglib")
 
 class MusicLooper:
     def __init__(

pymusiclooper/playback.py

@@ -3,11 +3,13 @@
 import threading
 
 import numpy as np
-import sounddevice as sd
+import lazy_loader as lazy
 from rich.progress import BarColumn, Progress, TextColumn
 
 from .console import rich_console
 
+# Lazy-load sounddevice
+sd = lazy.load("sounddevice")
 
 class PlaybackHandler:
     def __init__(self) -> None:

pymusiclooper/youtube.py

@@ -1,6 +1,8 @@
 import os
 
-import yt_dlp
+import lazy_loader as lazy
+
+yt_dlp = lazy.load("yt_dlp")
 
 
 class YtdLogger: