What are iterators and generators in Python?

What are iterators and generators in Python?

Iterators are objects that allow you to traverse through a collection, like a list, without exposing the underlying structure. Generators are a type of iterator that are defined using a function and the 'yield' statement.

Can you give me an example of a generator?

Sure! Here's a simple generator that yields the first three numbers:

def count_up_to(n):
    count = 1
    while count <= n:
        yield count
        count += 1

You can use it like this:

for number in count_up_to(3):
    print(number)

How do iterators differ from lists?

Iterators do not store their contents in memory; they generate items on the fly, which makes them more memory efficient than lists, especially for large datasets.

When should I use a generator instead of a list?

Use a generator when you want to iterate over a large dataset without loading everything into memory at once, or when you want to create an infinite sequence.