my personal tic-tac-toe project for the Complete Python Bootcamp/ Jose Portilla (Udemy)

tictactoe.py

#matrix map of the board is not a real matrix ;-)
#initialized to 0 <-> empty board
mat=[0, 0, 0,
     0, 0, 0,
     0, 0, 0]

#map_board to map the index of the input in the matrix map
map_board=['A1', 'B1', 'C1',
           'A2', 'B2', 'C2',
           'A3', 'B3', 'C3']


#function that displays the board after
#each valid position entered
def show_board(matrix):
    head=" A B C"
    inter=" -+-+-"

    print(head)
    print("1"+matrix[0]+"|"+matrix[1]+"|"+matrix[2])
    print(inter)
    print("2"+matrix[3]+"|"+matrix[4]+"|"+matrix[5])
    print(inter)
    print("3"+matrix[6]+"|"+matrix[7]+"|"+matrix[8])

#function that modifies the current matrix map prior to display
def map_matrix(matrix):
    mapped_matrix=[' ']*9
    for i in range(len(matrix)):
        if matrix[i]==1:
            mapped_matrix[i]='X' #1 encodes 'X'
        if matrix[i]==2:
            mapped_matrix[i]='O' #2 encodes 'O'
    return mapped_matrix         #0 encodes ' '

#function that test each line, row and diagonal
#for the presence of X or O (not 0)
#and returns the id of winner
def test_win(mat):
    if mat[0]==mat[1]==mat[2]!=0 or mat[0]==mat[3]==mat[6]!=0:
    #test 1st line and 1st column
        return mat[0]
    elif mat[3]==mat[4]==mat[5]!=0 or mat[1]==mat[4]==mat[7]!=0:
   #test 2nd line and 2nd column
        return mat[4]
    elif mat[6]==mat[7]==mat[8]!=0 or mat[2]==mat[5]==mat[8]!=0:
   #test 3rd line and 3rd column
        return mat[8]
    elif mat[0]==mat[4]==mat[8]!=0 or mat[2]==mat[4]==mat[6]!=0:
    #test both diagonals
        return mat[4]
    else:
        return False

#main process
    
show_board(map_matrix(mat))
turn=1 #player round

while sum(mat)<13: #while board is not completely filled
    print("PLAYER ", turn)
    position=input("position ?")
    
    if position.upper() not in map_board or mat[map_board.index(position.upper())] !=0 :
        continue
    else:
        mat[map_board.index(position.upper())]=turn

    if turn==1:
        turn=2
    else:
        turn=1

    show_board(map_matrix(mat))

    if test_win(mat):
        print("BRAVO PLAYER {player} !!!".format(player=test_win(mat)))
        break
print("GAME COMPLETE!")