Skip phoneme cache pre-compute if the path exists

TTS/tts/models/base_tts.py

@@ -1,6 +1,6 @@
+import os
 from typing import Dict, List, Tuple
 
-import numpy as np
 import torch
 from coqpit import Coqpit
 from torch import nn
@@ -184,7 +184,11 @@ class BaseTTS(BaseModel):
                 else None,
             )
 
-            if config.use_phonemes and config.compute_input_seq_cache:
+            if (
+                config.use_phonemes
+                and config.compute_input_seq_cache
+                and not os.path.exists(dataset.phoneme_cache_path)
+            ):
                 # precompute phonemes to have a better estimate of sequence lengths.
                 dataset.compute_input_seq(config.num_loader_workers)
             dataset.sort_items()