Update modeling_mplug_owl2.py

modeling_mplug_owl2.py

@@ -32,6 +32,8 @@ from transformers.modeling_outputs import CausalLMOutputWithPast
 from .configuration_mplug_owl2 import MPLUGOwl2Config, MplugOwlVisionConfig, MplugOwlVisualAbstractorConfig
 from .visual_encoder import MplugOwlVisionModel, MplugOwlVisualAbstractorModel
 from .modeling_llama2 import replace_llama_modality_adaptive
+from .modeling_attn_mask_utils import _prepare_4d_causal_attention_mask
+
 IGNORE_INDEX = -100
 IMAGE_TOKEN_INDEX = -200
 DEFAULT_IMAGE_TOKEN = "<|image|>"