The len() function in Python is used to get the length or the number of items in a sequence such as a string, list, tuple, dictionary, or set.

        For example, if we have a list of numbers, we can use the len() function to get the number of elements in the list:

numbers = [1, 2, 3, 4, 5]
print(len(numbers))  # Output: 5

        Similarly, if we have a string, we can use the len() function to get the number of characters in the string:

string = "Hello, World!"
print(len(string))  # Output: 13

        The len() function can also be used with other built-in Python data structures like tuples, dictionaries, and sets to get their lengths.

        In summary, the len() function is a useful built-in Python function for getting the length or the number of items in a sequence.