9-运算符-成员运算符in，not in

in 是否作为成员在容器中存在

s = "hello"
print("e" in s)  # True
print("w" in s)  # False

字典
in 判断目标是否作为key存在于字典中

data = {
    "error": 1001,
    "errmsg": "类型有误！"
}

print("error" in data) # error是字典data的key  True
print("data" in data)  # False，注意是key！！！ False

列表，元组

data = ["小明", "小红"]
print( "小明" in data)  # True

集合

data = {"小明", "小红"}
print( "小红" in data)  # True

not in 判断是否不是容器的成员

data = {
    "data": {"id":1, "title":"商品标题", "price": 13.6}
}
print("error" not in data)  # True