Permutation Problem

solution.py

#!/usr/bin/env python

def solution(N, S):
    reserved_seats = S.split(" ")
    seatMarkers= ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K']
    count = 0
    formatted = []
    seats = []
    # Creation of list of seats
    for row in range(N):
        for seatMarker in seatMarkers:
            seats.append("{}{}".format(seatMarker, row + 1))
    # Format the list into list of sets: 3 seats, 4 seats, 3 seats
    for i in range(0, len(seats), 10):
        formatted.append(seats[i: i+ 3])
        formatted.append(seats[i+3:i+7])
        formatted.append(seats[i+7:i+10])
    # Remove reserved seats
    for seat in formatted:
        for reserved_seat in reserved_seats:
            try:
                seat.remove(reserved_seat)
            except ValueError:
                pass
    # Count available seats
    for seats in formatted:
        if len(seats) >= 3:
            count += 1
    return count