input: Write a function to create a Text-to-Speech Python application that reads out a given sentence. The function should initialize a pyttsx3 engine, say the given sentence, and run the engine to wait for the speech to complete.
  assert text_to_speech("Hello, this is a simple sentence")==None
  assert text_to_speech("Welcome to our application")==None
output: import pyttsx3
  
  def text_to_speech(sentence):
      engine = pyttsx3.init()
      engine.say(sentence)
      engine.runAndWait()