espeak text to speech sounds very weird on ubuntu 20.04 LTS

I am bit new to linux and I tried to run this python code. At the first time it asked me to install libespeak-dev and try to run the code again. After installing it when I ran the code the sound was very weird and very robotic and it was terrible to listen. Here is the code:

import pyttsx3

engine = pyttsx3.init()

def speak(text):

speak("Hello World and this is a test.")

For some reasons I am unable to attach the mp3 file to tell how terrible it sounds. By the way I am using Ubuntu 20.04 LTS which comes with default installation of python 3.8.5. Is there any fix to this? Because it sounds very bad. Thanks in advance...