deal with exceptions of link_wav.py

如果遇到已存在的软链接则跳过，如果在dump中找不到这个符号则删除dump_finetune中的文件。

utils/link_wav.py

@@ -58,9 +58,15 @@ def main():
             mel_path = output_dir / ("raw/" + name)
             gen_mel = np.load(mel_path)
             wave_name = utt_id + "_wave.npy"
-            wav = np.load(old_dump_dir / sub / ("raw/" + wave_name))
-            os.symlink(old_dump_dir / sub / ("raw/" + wave_name),
-                       output_dir / ("raw/" + wave_name))
+            try:
+                wav = np.load(old_dump_dir / sub / ("raw/" + wave_name))
+                os.symlink(old_dump_dir / sub / ("raw/" + wave_name),
+                        output_dir / ("raw/" + wave_name))
+            except FileNotFoundError:
+                print("delete " + name + " because it cannot be found in the dump folder")
+                os.remove(output_dir / "raw" / name)
+            except FileExistsError:
+                print("file " + name + " exists, skip.")     
             num_sample = wav.shape[0]
             num_frames = gen_mel.shape[0]
             wav_path = output_dir / ("raw/" + wave_name)