Added assertion to check speakers map was found

Author: OscarVanL

examples/fastspeech2_libritts/fastspeech2_dataset.py

@@ -59,7 +59,7 @@ def __init__(
         f0_load_fn=np.load,
         energy_load_fn=np.load,
         mel_length_threshold=0,
-        speakers_map
+        speakers_map=None
     ):
         """Initialize dataset.
 
@@ -98,6 +98,8 @@ def __init__(
             == len(energy_files)
         ), f"Number of charactor, mel, duration, f0 and energy files are different"
 
+        assert speakers_map == None, f"No speakers map found. Did you set --dataset_mapping?"
+
         if ".npy" in charactor_query:
             suffix = charactor_query[1:]
             utt_ids = [os.path.basename(f).replace(suffix, "") for f in charactor_files]