Combining Iterables with Fillvalue

The function is used to combine multiple iterable objects into an iterator, and fill in missing values with fillvalue if the length of the iterable objects is inconsistent.

Technology Stack : itertools

Code Type : Function

Code Difficulty : Intermediate

                
                    
def zip_longest(*iterables, fillvalue=None):
    "Make an iterator that aggregates elements from each of the iterables.
    If the iterables are of uneven length, missing values are filled-in with fillvalue.
    Parameters
    ----------
    iterables : sequence or iterable
        An iterable of iterables.
    fillvalue : optional
        The value to use for missing values in the iterables.
    Returns
    -------
    iterator
        An iterator that produces tuples containing elements from the iterables.
    Examples
    --------
    >>> from itertools import zip_longest
    >>> list(zip_longest([1, 2, 3], [4, 5], fillvalue=0))
    [(1, 4, 0), (2, 5, 0), (3, None, 0)]
    >>> list(zip_longest('abc', 'de', fillvalue='-'))
    [('a', 'd', '-'), ('b', 'e', '-'), ('c', None, '-')]
    """
    from itertools import zip_longest as _zip_longest
    return _zip_longest(*iterables, fillvalue=fillvalue)