python function that returns cartesian prodict of two lists containing only pairs

product_of_pairs.py

def product_of_pairs(iterable1, iterable2, item_sorting_key=None):
    """Function that returns cartesian product of two lists. Output is filtered to contain only pairs, where pair
    means item cannot be with itself and AB == BA.
    Example:
        >>> product_of_pairs('ab', 'ab')
        {('a', 'b')}
    """
    return {
        tuple(sorted((item1, item2), key=item_sorting_key))
        for item1 in iterable1
        for item2 in iterable2
        if item1 != item2
    }