def countVowels(word):
    total = 0
    for c in word.lower():
        if c in 'aeiou':
            total += 1
    return total


# or using clever comprehension syntax and the fact that 
# True is treated as value 1 and False as value 0 in a sum

def countVowels(word):
    return sum(c in 'aeiou' for c in word.lower())