What are iterators in Python 3 and how do I use them?

What are iterators in Python 3 and how do I use them?

Iterators in Python 3 are objects that allow you to traverse through a collection, like lists or tuples, without needing to know the underlying structure. You can use the iter() function to create an iterator and the next() function to access elements.

Can you give me an example of how to create an iterator?

Sure! Here's a simple example:

my_list = [1, 2, 3]
my_iterator = iter(my_list)

print(next(my_iterator))  # Output: 1
print(next(my_iterator))  # Output: 2

What happens when I reach the end of the iterator?

When you reach the end of an iterator and call next() again, it raises a StopIteration exception. You can handle this using a try-except block.

How can I use a for loop with an iterator?

You can use a for loop directly with an iterator. For example:

for item in my_iterator:
    print(item)

This will print each item until the iterator is exhausted.