def inventory_report(seq):
    """
    prints the number of unique names of items, avg price,
    avg weight, and avg flammability of a list of Product class
    objects
    """
    num_prod = len(seq)

    names = set()
    avg_price = 0
    avg_weight = 0
    avg_flam = 0
    for prod in seq:
        names.add(prod.name)
        avg_price += prod.price
        avg_weight += prod.weight
        avg_flam += prod.flammability

    avg_price = avg_price / num_prod
    avg_weight = avg_weight / num_prod
    avg_flam = avg_flam / num_prod

    print("ACME Inventory Report \n")
    print(f"Number of Unique Products {len(names)} \n")
    print(f"Average Price: {avg_price} \n")
    print(f"Average Weight: {avg_weight} \n")
    print(f"Average Flammability: {avg_flam} \n")

    return None