example_v2.py

# Number of queens
print("Enter the number of queens")
N = int(input())

# chessboard
# NxN matrix with all elements 0
board = [[0]*N for _ in range(N)]


def is_attack(i, j):
    # checking if there is a queen in row or column
    for k in range(0, N):
        if board[i][k] == 1 or board[k][j] == 1:
            return True
    # checking diagonals
    for k in range(0, N):
        for l in range(0, N):
            if (k+l == i+j) or (k-l == i-j):
                if board[k][l] == 1:
                    return True
    return False


def N_queen(n):
    # if n is 0, solution found
    if n == 0:
        return True
    for i in range(0, N):
        for j in range(0, N):
            '''checking if we can place a queen here or not
            queen will not be placed if the place is being attacked
            or already occupied'''
            if (not(is_attack(i, j))) and (board[i][j] != 1):
                board[i][j] = 1
                # recursion
                # wether we can put the next queen with this arrangment or not
                if N_queen(n-1) == True:
                    return True
                board[i][j] = 0

    return False


N_queen(N)
for i in board:
    print(i)