Python MiniMax AI (Easy Mode AI)

import math
from random import randint
#Setup Variable
Turn = None
AI = None
Player = None
PrevPlayed = None
Board = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
]
VaildTeam = ["O", "X"]
# Game Function
def DrawBoard():
    global Board
    print("-"*13)
    for i in range(3):
        print(f"| {Board[i][0]} | {Board[i][1]} | {Board[i][2]} |")
    print("-"*13)
def ChooseTeam():
    global Player, AI, VaildTeam
    while True:
        PlayerInput = input("Choose You Team O or X : ").upper()
        if PlayerInput in VaildTeam:
            Player = PlayerInput
            AI = "O" if Player=="X" else "O"
            break
        else:
            print("Invaild Team Choose Again!")
            continue

def StartTurn():
    global Turn
    n=randint(1,2)
    Turn = Player if n==1 else AI

def IsAbleToFill(row:int, col:int)-> bool:
    global Board
    return type(Board[row][col]) == int

def IsTie() -> bool:
    global Board
    return all([ type(Board[i][j]) != int for i in range(3) for j in range(3)])

def IsGameOver() -> bool:
    global Board
    for i in range(3):
        # Left or Right
        if Board[i][0] == Board[i][1] and Board[i][1] == Board[i][2]:
            return True
        #Up and Down
        elif Board[0][i] == Board[1][i] and Board[1][i] == Board[2][i]:
            return True
    # More
    if Board[0][0] == Board[1][1] and Board[1][1] == Board[2][2]:
        return True
    elif Board[0][2] == Board[1][1] and Board[1][1] == Board[2][0]:
        return True
    return False

def PlayerFill(row : int, col : int):
    global Player, Board
    if IsAbleToFill(row, col):
        Board[row][col] = Player
    else:
        return

def AutoPlayRound():
    global Turn, Player, AI, Board, PrevPlayed
    # AutoPlay Function
    def PlayerPlay():
        global Board, AI, Player, PrevPlayed, Turn
        row, col= None, None
        while True:
            PlayerInput = int(input("Choose Board to Fill in 1-9 : "))
            if PlayerInput > 9:
                print("Invaild Input Try Again")
                continue
            if PlayerInput <= 3:
                row, col = 0, PlayerInput-1
                if not IsAbleToFill(row, col):
                    print("Board Already Filled Choose Another")
                    continue
                PlayerFill(row, col)
                break
            elif PlayerInput <= 6:
                row, col = 1, PlayerInput-4
                if not IsAbleToFill(row, col):
                    print("Board Already Filled Choose Another")
                    continue
                PlayerFill(row, col)
                break
            elif PlayerInput <= 9:
                row, col = 2, PlayerInput-7
                if not IsAbleToFill(row, col):
                    print("Board Already Filled Choose Another")
                    continue
                PlayerFill(row, col)
                break
        PrevPlayed = Player
        Turn = AI

    def AIPlay():
        global Board, AI, Player, PrevPlayed, Turn
        print("AI is Thinking and Choosing...")
        AIFill()
        PrevPlayed = AI
        Turn = Player
    if Turn == Player:
        PlayerPlay()
    else:
        AIPlay()
#AI MiniMax Function
def MiniMaxCheckWinner():
    global Board
    for i in range(3):
        # Left or Right
        if Board[i][0] == Board[i][1] and Board[i][1] == Board[i][2]:
            return Board[i][0]
        #Up and Down
        elif Board[0][i] == Board[1][i] and Board[1][i] == Board[2][i]:
            return Board[0][i]
    # More
    if Board[0][0] == Board[1][1] and Board[1][1] == Board[2][2]:
        return Board[0][0]
    elif Board[0][2] == Board[1][1] and Board[1][1] == Board[2][0]:
        return Board[0][2]
    return None

def MiniMax(ismaxing : bool) -> int:
    global AI, Player, Board
    if MiniMaxCheckWinner() == AI: return 1
    if MiniMaxCheckWinner() == Player: return -1
    if IsTie(): return 0
    # Minimax Main Block Code
    if ismaxing:
        maxscore = -math.inf
        for i in range(3):
            for j in range(3):
                if IsAbleToFill(i, j):
                    temp = Board[i][j]
                    Board[i][j] = AI
                    score = MiniMax(False)
                    if score > maxscore: maxscore = score
                    Board[i][j] = temp
        return maxscore
    else:
        minscore = math.inf
        for i in range(3):
            for j in range(3):
                if IsAbleToFill(i, j):
                    temp = Board[i][j]
                    Board[i][j] = AI
                    score = MiniMax(True)
                    if score < minscore: minscore = score
                    Board[i][j] = temp
        return minscore

def AIFill():
    global AI, Player
    #Setup Variable for AI
    bestscore = -math.inf
    bestfill = None
    for i in range(3):
        for j in range(3):
            if IsAbleToFill(i, j):
                score = MiniMax(False)
                if score > bestscore:
                    bestscore = score
                    bestfill = (i, j)
    # AI Fill Here
    Board[bestfill[0]][bestfill[1]] = AI
# Main Game Code

ChooseTeam()
StartTurn()
while True:
    DrawBoard()
    if IsGameOver():
        print(f"Game Over Winner : {PrevPlayed}")
        break
    if IsTie():
        print("Game Tie!")
        break
    AutoPlayRound()