converting individual digits to string

Question

I think i\'m very close but i cant seem to fix my issues. I need a function that takes a 10-digit input from user (me) and sets each letter to is numeric value.

Example:

Answer 1

def main(phone_number):
    digits = ["2", "3", "4", "5", "6", "7", "8", "9"]
   numeric_phone=" "
   for ch in phone_number:
       if ch.isalpha():
           if ord(ch) >= 97:
               ch = +2 (ord(ch)-97)/3
           else:
               ch = +2 (ord(ch)-65)/3
       numeric_phone= numeric_phone+ch
   print (numeric_phone)

Use ord() to convert chars to their ASCII values and then get the right number.