from itertools import product

s='метро'

s0='мтр'

s3='ео'

words=[]

for w in product(s,repeat=4):

if (w[0] in s0) and (w[3] in s3):

words.append(w)

print(len(words))

import itertools

alphabet = "МЕТРО"

con = "МТР"

vol = "ЕО"

ar = itertools.product(alphabet, repeat=4) #Раз­ме­ще­ние с по­вто­ре­ни­ем

arl = []

for i in ar:

arl.append(list(i))

count = 0

for e in arl:

if e[0] in con and e[-1] in vol:

count += 1

print(count)