tictactoe.py

def analyze(x):
    board=[list(x[0:3]),list(x[3:6]),list(x[6:9])]
    for i in range(3):
        if all(j[i] == "X" for j in board) or all(board[i][j] == "X" for j in range(3)):
            return "X"
        if all(j[i] == "O" for j in board) or all(board[i][j] == "O" for j in range(3)):
            return "O"
    #Check diagnals
    if board[0][0] == board[1][1] == board[2][2] or board[0][2] == board[1][1] == board[2][0]:
        if board[1][1] != "#":
            return board[1][1]
    return "#"
    
print(analyze(input()))