Codewars - Highest Scoring Word
Indeed, the values dictionary looks unnecessary. Using a built-in function ord you could compute the letter score with ord(letter) - ord('a') + 1. One may argue that it is even faster than a dictionary lookup, but in this case the timing difference is rather marginal.



With Python you should avoid rolling explicit loops. For example, collecting the word values is more idiomatically expressed as a comprehension:

    word_values = [word_value(word) for word in word_list]


Similarly, instead of

    for letter in input_word:
        value += values[letter]


consider functools.reduce:

    value = functools.reduce(lambda x, y: x + ord(y) - ord('a') + 1, input_word, 0)