A substring of a string is called a slice. Selecting a slice is similar to selecting a character:
singers = "Peter, Paul, and Mary"
print(singers[0:5])
print(singers[7:11])
print(singers[17:21])
The slice operator [n:m] returns the part of the string from the n’th character to the m’th character, including the first but excluding the last. In other words, start with the character at index n and go up to but do not include the character at index m. This behavior may seem counter-intuitive but if you recall the range function, it did not include its end point either.
