fix for japanese

app.py

@@ -483,6 +483,11 @@ def generate_speech(history):
         sentence = sentence.replace("(", " ")
         sentence = sentence.replace(")", " ")
         
+        if len(sentence)==0:
+            #possible after cleanup sentence is empty
+            #e.g Kana then romaji in brackets
+            continue
+        
         # A fast fix for last chacter, may produce weird sounds if it is with text
         if (sentence[-1] in ["!", "?", ".", ","]) or (sentence[-2] in ["!", "?", ".", ","]):
             # just add a space