Sorting lists in Python

Using sorted() Function:

The built-in sorted() function returns a new list containing all the elements of the original list sorted in the specified order (either ascending, which is default, or descending).

my_list = [3, 1, 4, 1, 5, 9, 2, 6, 5]
sorted_list = sorted(my_list)
print(sorted_list)  # Output: [1, 1, 2, 3, 4, 5, 5, 6, 9]

For sorting in descending order, you can use the reverse=True argument:

sorted_list_desc = sorted(my_list, reverse=True)
print(sorted_list_desc)  # Output: [9, 6, 5, 5, 4, 3, 2, 1, 1]

Using .sort() Method:

The .sort() method sorts the elements of a list in-place and returns None. This modifies the original list.

my_list = [3, 1, 4, 1, 5, 9, 2, 6, 5]
my_list.sort()
print(my_list)  # Output: [1, 1, 2, 3, 4, 5, 5, 6, 9]

For sorting in descending order:

my_list.sort(reverse=True)
print(my_list)  # Output: [9, 6, 5, 5, 4, 3, 2, 1, 1]

Using a Custom Key Function:

Both sorted() and .sort() accept a key parameter that allows you to specify a function to determine the sorting order. The function should take a single argument and return a value that will be used for sorting purposes.

For example, if you have a list of strings and you want to sort them by their length:

my_str_list = ["apple", "banana", "cherry", "date"]
sorted_by_length = sorted(my_str_list, key=len)
print(sorted_by_length)  # Output: ['date', 'apple', 'cherry', 'banana']
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