Fix string case

In this Kata, you will be given a string that may have mixed uppercase and lowercase letters and your task is to convert that string to either lowercase only or uppercase only based on:

• make as few changes as possible.
• if the string contains equal number of uppercase and lowercase letters, convert the string to lowercase.

For example:

solve("coDe") = "code". Lowercase characters > uppercase. Change only the "D" to lowercase.
solve("CODe") = "CODE". Uppercase characters > lowecase. Change only the "e" to uppercase.
solve("coDE") = "code". Upper == lowercase. Change all to lowercase.

More examples in test cases. Good luck!

 

Solution:

def solve(s):
    return sum([i.islower() for i in s]) >= len(s)/2 and s.lower() or s.upper()