add global keyword

app.py

@@ -66,9 +66,11 @@ def main():
                 uses cached list of speakers for the given model name
                 or loads the addon and checks what are the speakers.
                 """
+                global model_to_speakers
                 if model_name_str in model_to_speakers:
                     speakers = model_to_speakers[model_name_str]
                 else:
+                    global tts, cur_model_path
                     # need to load this model to learn the list of speakers
                     model_path = os.path.join(model_repo_dir, model_name_str)
                     tts = TTS(model_path)
@@ -99,6 +101,7 @@ def main():
                 logging.info("text, model name or speaker are not provided")
                 return None
             expected_model_path = os.path.join(model_repo_dir, model_name_str)
+            global tts, cur_model_path
             if expected_model_path != cur_model_path:
                 # reload model
                 tts = TTS(expected_model_path)