Iterators and large lists.

list_02_indices.py

import typing


def get_indices(the_list: list, test_value: object) -> typing.Iterable[int]:
    """
    Returns the indices of matching list items.
    Uses a generator to create an iterator.
    Args:
        the_list: the list containing search elements
        test_value: what we want to find

    Returns: the index of matching list items
    >>> print(list(get_indices("The jolly green giant", "e")))
    [2, 12, 13]
    """

    generator = (key for key, val in enumerate(the_list) if test_value == val)
    for key in generator:
        yield key