Function _demo_mm_inputs

Create a superset of inputs needed to run test or train batches. Args: input_shape (tuple): input batch dimensions num_items (None | List[int]): specifies the number of boxes in each batch item num_classes (int): number of different

(input_shape=(1, 3, 300, 300),
                    num_items=None, num_classes=10,
                    with_semantic=False)