chore: import upstream snapshot with attribution

modules/pe/__init__.py

@@ -0,0 +1,18 @@
+from utils import hparams
+
+from .pm import ParselmouthPE
+from .pw import HarvestPE
+from .rmvpe import RMVPE
+
+
+def initialize_pe():
+    pe = hparams['pe']
+    pe_ckpt = hparams['pe_ckpt']
+    if pe == 'parselmouth':
+        return ParselmouthPE()
+    elif pe == 'rmvpe':
+        return RMVPE(pe_ckpt)
+    elif pe == 'harvest':
+        return HarvestPE()
+    else:
+        raise ValueError(f" [x] Unknown f0 extractor: {pe}")