为了..。if语句后的in语句

fruits = ['apple', 'banana', 'orange']
if 'apple' in fruits:
    print("苹果在水果列表中")
else:
    print("苹果不在水果列表中")

numbers = (1, 2, 3, 4, 5)
if 3 in numbers:
    print("3在元组中")
else:
    print("3不在元组中")

person = {'name': 'Alice', 'age': 25, 'city': 'Beijing'}
if 'age' in person:
    print("年龄是{}岁".format(person['age']))
else:
    print("年龄信息不存在")