Python 3 Day 3

Day3 Python3
Part 1
alfa=list(map(chr,[*range(97,123),*range(65,91)]))
prior=0
for s in open('input.txt'):
    for x in alfa:
        if x in s[:int(len(s) / 2)] and x in s[int(len(s) / 2):]:
            prior += alfa.index(x)+1
print(prior)
Part 1 one line
print(sum([int(list(map(chr,[*range(97,123),*range(65,91)])).index(x)+1) for s in open('input.txt') for x in list(map(chr,[*range(97,123),*range(65,91)]))  if (x in s[:int(len(s) / 2)] and x in s[int(len(s) / 2):])]))

Part 2
prior=0
x=[line.strip() for line in open('input.txt')]
lista = [x[i:i+3] for i in range(0,len(x),3)]
print(lista)
for sub in lista:
    for x in alfa:
        if all(x in sub[i] for i in range(3)):
            prior += alfa.index(x) + 1
print(prior)
Part 2 one line
print(sum([(list(map(chr,[*range(97,123),*range(65,91)])).index(y)+1) for x in list(list(line.strip() for line in open('input.txt'))[i:i+3] for i in range(0,len(list(line for line in open('input.txt'))),3)) for y in (list(map(chr,[*range(97,123),*range(65,91)]))) if all(y in x[i] for i in range(3))]))