How to use pyttsx in a python thread - multithreading

Question

I am working with pyttsx3 for text-to-speech. I realized that I can use it within a thread (or I am doing something wrong). Do you know why?
Code Example:
from threading import Thread
import pyttsx3
def myfunc():
engine = pyttsx3.init()
engine.say("ok")
engine.runAndWait()
t = Thread(target=myfunc)
t.start()
Error:
File "/usr/local/Cellar/python3/3.6.4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/threading.py", line 916, in _bootstrap_inner
self.run()
File "/usr/local/Cellar/python3/3.6.4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/threading.py", line 864, in run
self._target(*self._args, **self._kwargs)
File "test.py", line 9, in myfunc
engine.runAndWait() #blocks
File "/usr/local/lib/python3.6/site-packages/pyttsx3/engine.py", line 188, in runAndWait
self.proxy.runAndWait()
File "/usr/local/lib/python3.6/site-packages/pyttsx3/driver.py", line 204, in runAndWait
self._driver.startLoop()
File "/usr/local/lib/python3.6/site-packages/pyttsx3/drivers/nsss.py", line 33, in startLoop
AppHelper.runConsoleEventLoop()
File "/usr/local/lib/python3.6/site-packages/PyObjCTools/AppHelper.py", line 241, in runConsoleEventLoop
nextfire = nextfire.earlierDate_(soon)
AttributeError: 'NoneType' object has no attribute 'earlierDate_'

Answer 1

The error seems to be that it doesn't run in threads on osx. Here are some examples that might work well:
If you just need to convert text into speech, you can use os.system('say %s'):
import os
def myfunc():
os.system('say ok')
gTTS or Google's TextToSpeech engine, supports 64 languages, including italian. Usage:
from gtts import gTTS
import os
tts = gTTS(text='Good morning', lang='it')
tts.save("good.mp3")
os.system("mpg321 good.mp3")

Answer 2

I think pyttsx3 can't make a sound in multiple threads (it's OK to make a sound only once). If you want to make a sound in multiple threads, the Macos system should use the say command.
Other operating systems should also have corresponding commands
import sys
import os
import threading
print('threading1:',threading.activeCount())
text = 'Please start'
def myfunc():
while True:
# os.system('say another')
# os.system('say -v Daniel "another"')
# os.system('say -v Daniel "[[rate 160]] another"') # 速度默认200
os.system('say -v Daniel -r 140 "{}"'.format(text))
os.system('say -v Samantha -r 140 "{}"'.format(text))
# print(111)
loopThread = threading.Thread(target=myfunc, name='backgroundMusicThread')
loopThread.daemon = True
loopThread.start()
print('threading2:',threading.activeCount())
while True:
text = input('input:\n')
if text == 'end':
sys.exit()