How to shift vowels in input string with Python

Question

I am trying to write a function that would let me shift the individual letters in a string. The string comes from the input.

I'm looking at vowels so "a, e, i, o, u"

I would like the individual letter to be shifted one to the right. i.e the world "me" would become "mi" as i is the next letter after e.

this is what I have so far:

import random
vowels = ("a", "e", "i", "o", "u")

message = input("Enter a string")

new_message = ""

for letter in message:
    if letter not in vowels:
        new_message += letter
    else:
        new_message += random.choice(vowels)
        
print(new_message)

However, this randomizes the changing of the individual vowels, what would be the best way to make it shift to the next letter?

Answer 1

If you want to translate the whole string, then I would look at str.translate.

Here is a simple example working with your vowels:

>>> v = "aeiou"
>>> vDict = {v[i]: v[(i+1)%len(v)] for i in range(len(v))}
>>> vDict
{'a': 'e', 'e': 'i', 'i': 'o', 'o': 'u', 'u': 'a'}
>>> "This is a test-string. hope it works!".translate(str.maketrans(vDict))
'Thos os e tist-strong. hupi ot wurks!'