How to use indexing in Python?

In Python, you can use indexes to access elements in containers such as lists, tuples, and strings. Indexes are integers starting from 0 and represent the position of the element in the container.

For example, for a list:

my_list = [1, 2, 3, 4, 5]

We can access elements in a list using indexes. For example, to access the first element in a list, we can use index 0:

print(my_list[0])  # 输出：1

To access the third element in the list, you can use the index 2:

print(my_list[2])  # 输出：3

To access the last element in the list, you can use a negative index of -1.

print(my_list[-1])  # 输出：5

One can also access characters within a string using indexing. For example:

my_string = "Hello, World!"
print(my_string[0])  # 输出：H
print(my_string[-1])  # 输出：!

For tuples, the way to use indexes is the same as with lists. For example:

my_tuple = (1, 2, 3, 4, 5)
print(my_tuple[2])  # 输出：3