Rules regarding labels format: - if label_mode is int, the labels are an int32 tensor of shape (batch_size,). - if label_mode is binary, the labels are a float32 tensor of 1s and 0s of shape (batch_size, 1). - if label_mode is categorial, the labels are a float32 tensor of shape (batch_size, num_classes), representing a one-hot encoding of the class index.