Count letter differences of two strings

Question

This is the behaviour I want:

a: IGADKYFHARGNYDAA
c: KGADKYFHARGNYEAA
2 difference(s).

Answer 1

a = "IGADKYFHARGNYDAA" 
b = "KGADKYFHARGNYEAAXXX"
match_pattern = zip(a, b)                                 #give list of tuples (of letters at each index)
difference = sum (1 for e in zipped if e[0] != e[1])     #count tuples with non matching elements
difference = difference + abs(len(a) - len(b))            #in case the two string are of different lenght, we add the lenght difference