def corresponding_lists(x, y):
    """Returns True is both lists x and y have one to one mapping
        e.g:
            x = [12, 4, 12, 3]
            y = [44, 6, 44, 9]
            corresponding_lists(x, y) # True
    """
    unique_mapping_pairs = set(zip(x, y))
    unique_elements = set(y)
    return len(unique_mapping_pairs) == len(unique_elements)