How To Reverse a String in Python

Sometimes you may need to reverse a string. How to do it in Python?

To reverse a string all we need is the slice operator with the step set to -1. Have a look:

>>> text = "I like music."
>>> rtext = text[::-1]
>>> rtext
'.cisum ekil I'

Let’s write a function that tests if a string is a palindrome. It is if it reads the same in both directions, like “gig” or “kayak”. You can neglect capitalization and white spaces:

def is_palindrome(text):
    text_lowercase = text.lower() # set all characters to lowercase
    text_no_spaces = "".join(text_lowercase.split()) # remove spaces
    if text_no_spaces == text_no_spaces[::-1]:
        print(f"'{text}' is a palindrome.")
    else:
        print(f"'{text}' is not a palindrome.")
    
is_palindrome("hello")
is_palindrome("A Santa at Nasa")

Output:

'hello' is not a palindrome.
'A Santa at Nasa' is a palindrome.

As you can see, there’s no magic involved. If you want to play with this function a bit more, here are some palindromes that you can test. They should all give you a positive result:

deed, radar, level, civic, racecar

I’m sure you can come up with some more of your own.

Here’s the video version: