What is iterator in Python - Interview Question

An iterator in Python is an object that represents a stream of data. It implements the iterator protocol, which consists of two methods: __iter__() and __next__(). The __iter__() method returns the iterator object itself, while the __next__() method returns the next item from the stream. When there are no more items to return, it raises the StopIteration exception.

Iterators in Python are commonly used in loops to iterate over sequences like lists, tuples, strings, and more. They provide a way to access elements of a collection one by one without needing to know the underlying implementation details.

Understanding iterators is essential for mastering Python programming and leveraging its powerful features for processing data efficiently.