queens.py

def check(row,column,board):
    for i in range(N):
        if board[row][i] == 'Q':
            return False
    return True

def solve_queen(current_column, board):
    if current_column == -1:
        print board
        return True

    for i in range(len(board)):
        if check(i,current_column,board):
            board[i][current_column] = 'Q'
            if not solve_queen(current_column-1,board):
                board[i][current_column] = '*'

N = 4

board = [[None]*4]*4
print solve_queen(N-1,board)