Python如何检查除特定值以外的内容是否为字母数字

def check_alnum(string, exclude):
    for char in string:
        if char not in exclude and not char.isalnum():
            return False
    return True

exclude = ['!', '@', '#', '$', '%']  # 需要排除的特定值
string1 = "abc123"  # 只包含字母和数字，返回True
string2 = "abc123!"  # 包含特定值"!"，返回False
string3 = "abc123@"  # 包含特定值"@"，返回False

print(check_alnum(string1, exclude))
print(check_alnum(string2, exclude))
print(check_alnum(string3, exclude))

True
False
False