Primes in python A-z A-Z letters

Question

In this problem you should read a set of words, where each word is composed only of letters in the a-z and A-Z range. Each letter has a specific value, the letter a is 1, the letter b is 2, and so on, down to the letter z, which is 26. Similarly, the letter A is 27, the letter B is 28 and the letter Z is 52.

You should write a program to determine whether a word is a prime word or not. A word is a prime word if the sum of its letters is a prime number.

I am in doubt of how to do it, I have already created the variables, the = []

for i in range(ord('a'), ord('z')+1):
    a.append(chr(i))

Answer 1

Just set a function that returns the number that represents each letter:

def get_ord_of_char(char):
  if 'a' <= char <= 'z':
    return ord(char) - ord('a') + 1
  else:
    return ord(char) - ord('A') + 27

Then calculate the sum of the numbers representing the word:

soma = sum(get_ord_of_char(char) for char in palavra)

And finally, check whether soma is a prime number. It would look like this:

palavra = 'teste'
soma = sum(get_ord_of_char(char) for char in palavra)
print('A palavra é prima' if is_prime(soma) else 'A palavra não é prima')

Just you implement the function is_prime that takes an integer number as a parameter.