How can I create a custom iterable in Python?

How can I create a custom iterable in Python?

To create a custom iterable in Python, you need to define a class with the __iter__() and __next__() methods.

Can you show me an example of a custom iterable?

Sure! Here's a simple example:

class MyIterable:
    def __init__(self, data):
        self.data = data
        self.index = 0

    def __iter__(self):
        return self

    def __next__(self):
        if self.index < len(self.data):
            result = self.data[self.index]
            self.index += 1
            return result
        else:
            raise StopIteration

my_iterable = MyIterable([1, 2, 3])
for item in my_iterable:
    print(item)

What happens if I forget to implement __iter__?

If you forget to implement __iter__, your class won't be recognized as an iterable, and you'll get a TypeError when trying to iterate over it.

Can I use generators instead of defining __next__?

Yes! You can use a generator function to create an iterable without explicitly defining __iter__ and __next__. Just use the yield statement.