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import itertools

def solve_24_game(nums):
    if not isinstance(nums, list) or len(nums) != 4:
        raise ValueError("input 4 number:")
    ops = ['+', '-', '*', '/']
    for p_nums in itertools.permutations(nums):
        for p_ops in itertools.product(ops, repeat=3):
            try:
                expr = f"({p_nums[0]}{p_ops[0]}{p_nums[1]}){p_ops[1]}{p_nums[2]}{p_ops[2]}{p_nums[3]}"
                if abs(eval(expr) - 24) < 1e-6: 
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass
            try:        # 形式: a op (b op c) op d
                expr = f"{p_nums[0]}{p_ops[0]}({p_nums[1]}{p_ops[1]}{p_nums[2]}){p_ops[2]}{p_nums[3]}"
                if abs(eval(expr) - 24) < 1e-6:
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass
            try:        # 形式: a op b op (c op d)
                expr = f"{p_nums[0]}{p_ops[0]}{p_nums[1]}{p_ops[1]}({p_nums[2]}{p_ops[2]}{p_nums[3]})"
                if abs(eval(expr) - 24) < 1e-6:
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass

            try:        # 形式: (a op b op c) op d (需要进一步细分括号)
                expr = f"(({p_nums[0]}{p_ops[0]}{p_nums[1]}){p_ops[1]}{p_nums[2]}){p_ops[2]}{p_nums[3]}"
                if abs(eval(expr) - 24) < 1e-6:
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass

            try:        # 例如: (a op (b op c)) op d
                expr = f"({p_nums[0]}{p_ops[0]}({p_nums[1]}{p_ops[1]}{p_nums[2]})){p_ops[2]}{p_nums[3]}"
                if abs(eval(expr) - 24) < 1e-6:
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass

            try:        # 形式: a op (b op c op d) (需要进一步细分括号)
                expr = f"{p_nums[0]}{p_ops[0]}(({p_nums[1]}{p_ops[1]}{p_nums[2]}){p_ops[2]}{p_nums[3]})"
                if abs(eval(expr) - 24) < 1e-6:
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass

            try:        # 例如: a op (b op (c op d))
                expr = f"{p_nums[0]}{p_ops[0]}({p_nums[1]}{p_ops[1]}({p_nums[2]}{p_ops[2]}{p_nums[3]}))"
                if abs(eval(expr) - 24) < 1e-6:
                    return expr
            except (ZeroDivisionError, SyntaxError):
                pass
    return None