索引和切片

my_numbers = (4, 5, 3, 9) print(my_numbers[-1]) print(my_numbers[-3])

my_numbers = (1, 1, 2, 3, 5, 8, 13, 21) print(my_numbers[2:5])

my_numbers = (1, 1, 2, 3, 5, 8, 13, 21) print(my_numbers[:3]) print(my_numbers[3:]) print(my_numbers[::]) # 也等同于 my_numbers[:]，返回一个副本 print(my_numbers[1:7:2])

my_numbers = (1, 1, 2, 3, 5, 8, 13, 21)

interval = slice(1, 7, 2) print(my_numbers[interval])

interval = slice(None, 3) print(my_numbers[interval] == my_numbers[:3])

from collections.abc import Sequence

class Items(Sequence): def init(self, *values): self._values = list(values)

1def __len__(self):
2    return len(self._values)
3
4def __getitem__(self, item):
5    return self._values.__getitem__(item)

print(range(1, 100)[25:50])