how to add variables to strings in python code example

Example 1: insert value in string python

>>> shepherd = "Martha"
>>> age = 34
>>> # Note f before first quote of string
>>> stuff_in_string = f"Shepherd {shepherd} is {age} years old."
>>> print(stuff_in_string)
Shepherd Martha is 34 years old.

Example 2: how to add a variable to an string

var str = "ello";
var letter = "h";
str = letter + str;