In Python, reversed() is a built-in function that returns a reverse iterator over a sequence. It takes a single argument, which can be a sequence (e.g. a list, tuple, or string) or an object that supports sequence operations.
The syntax of the reversed() function is as follows:
reversed(seq)
Here, seq is the sequence to be reversed.
The reversed() function returns a reverse iterator, which can be used to loop through the elements of the sequence in reverse order.
For example:
my_list = [1, 2, 3, 4, 5]
for i in reversed(my_list):
print(i)
Output:
5
4
3
2
1
In this example, reversed(my_list) returns a reverse iterator over the list my_list, which is then used in a for loop to print the elements of the list in reverse order.
Note that reversed() does not modify the original sequence. If you want to create a reversed copy of a sequence, you can use the [::-1] slicing syntax.
For example:
my_list = [1, 2, 3, 4, 5]
reversed_list = my_list[::-1]
In this example, my_list[::-1] creates a reversed copy of my_list, which is then assigned to reversed_list.
