bold a string message in python code example

Example: bold some letters of string in python

from __future__ import unicode_literals, print_function
from prompt_toolkit import print_formatted_text, HTML

print_formatted_text(HTML('<b>This is bold</b>'))
print_formatted_text(HTML('<i>This is italic</i>'))
print_formatted_text(HTML('<u>This is underlined</u>'))