from copy import deepcopy

def bin_pack(items, min_pm, max_pm, current_packing=None, solution=None):
    """Generate optimal packs of cables, the sum being between min and max capacity."""
    if current_packing is None:
        current_packing = []
    if not items:
        # Stop conditions: we have no item to fit in packages
        if solution is None or len(current_packing) < solution:
            # If our solution doesn't respect min_pm, it's not returned, return best known solution instead
            for pack in current_packing:
                if sum((item[3] for item in pack)) < min_pm:
                    return solution
            # Solutions must be cleanly copied because we pop and append in current_packing
            return deepcopy(current_packing)
        return solution
    # We iterate by poping items and inserting in a list of list of items
    item = items.pop()
    # Try to fit in current packages
    for pack in current_packing:
        if sum((item[3] for item in pack)) + item[3] <= max_pm:
            pack.append(item)
            solution = bin_pack(items, min_pm, max_pm, current_packing, solution)
            pack.remove(item)
    # Try to make a new package
    if solution is None or len(solution) > len(current_packing):
        current_packing.append([item])
        solution = bin_pack(items, min_pm, max_pm, current_packing, solution)
        current_packing.remove([item])
    items.insert(-1, item)
    return solution