Update tts.py

tts.py

@@ -92,7 +92,7 @@ class TextMapper(object):
         return text
 
 
-def synthesize(text, lang, speed=None):
+def synthesize(text=None, lang=None, speed=None):
     if speed is None:
         speed = 1.0
 
@@ -173,9 +173,9 @@ def synthesize(text, lang, speed=None):
 
 
 TTS_EXAMPLES = [
-    ["I am going to the store.", "eng (English)"],
-    ["안녕하세요.", "kor (Korean)"],
-    ["क्या मुझे पीने का पानी मिल सकता है?", "hin (Hindi)"],
-    ["Tanış olmağıma çox şadam", "azj-script_latin (Azerbaijani, North)"],
-    ["Mu zo murna a cikin ƙasar.", "hau (Hausa)"],
+    ["I am going to the store.", "eng (English)", 1.0],
+    ["안녕하세요.", "kor (Korean)", 1.0],
+    ["क्या मुझे पीने का पानी मिल सकता है?", "hin (Hindi)", 1.0],
+    ["Tanış olmağıma çox şadam", "azj-script_latin (Azerbaijani, North)", 1.0],
+    ["Mu zo murna a cikin ƙasar.", "hau (Hausa)", 1.0],
 ]