迭代
迭代，重复一定的算法，达到想要的目的。数学上二分法是很好的迭代例子
例子
x, y = p
print(x, y)
print(x)
data = ['ACME', 50, 123.45, (12, 18, 2023)]
name, shares, price, (day, month, year) = data
print(day)
注：若元素数量不足，会得到错误提示
用用不到的变量名丢弃特定值
data = ['ACME', 50, 123.45, (12, 18, 2023)]
_, shares, price, _ = data
print(data)
print(shares)
