def from_pretrained(cls, pretrained_model_name_or_path, *args, **kwargs):
        """
        Creates an instance of `PretrainedModel`. Model weights are loaded
        by specifying name of a built-in pretrained model, or a community contributed model,
        or a local file directory path.

        Args:
            pretrained_model_name_or_path (str): Name of pretrained model or dir path
                to load from. The string can be:

                - Name of a built-in pretrained model
                - Name of a community-contributed pretrained model.
                - Local directory path which contains model weights file("model_state.pdparams")
                  and model config file ("model_config.json").
            *args (tuple): Position arguments for model `__init__`. If provided,
                use these as position argument values for model initialization.
            **kwargs (dict): Keyword arguments for model `__init__`. If provided,
                use these to update pre-defined keyword argument values for model
                initialization. If the keyword is in `__init__` argument names of
                base model, update argument values of the base model; else update
                argument values of derived model.

        Returns:
            PretrainedModel: An instance of `PretrainedModel`.

        Example:
            .. code-block::

                from paddlenlp.transformers import BertForSequenceClassification

                # Name of built-in pretrained model
                model = BertForSequenceClassification.from_pretrained('bert-base-uncased')

                # Name of community-contributed pretrained model
                model = BertForSequenceClassification.from_pretrained('yingyibiao/bert-base-uncased-sst-2-finetuned')

                # Load from local directory path
                model = BertForSequenceClassification.from_pretrained('./my_bert/')
        """
        pretrained_models = list(cls.pretrained_init_configuration.keys())
        resource_files = {}
        init_configuration = {}

        # From built-in pretrained models
        if pretrained_model_name_or_path in pretrained_models:
            for file_id, map_list in cls.pretrained_resource_files_map.items():
                resource_files[file_id] = map_list[
                    pretrained_model_name_or_path]
            init_configuration = copy.deepcopy(
                cls.pretrained_init_configuration[
                    pretrained_model_name_or_path])
        # From local dir path
        elif os.path.isdir(pretrained_model_name_or_path):
            for file_id, file_name in cls.resource_files_names.items():
                full_file_name = os.path.join(pretrained_model_name_or_path,
                                              file_name)
                resource_files[file_id] = full_file_name
            resource_files["model_config_file"] = os.path.join(
                pretrained_model_name_or_path, cls.model_config_file)
        else:
            # Assuming from community-contributed pretrained models
            for file_id, file_name in cls.resource_files_names.items():
                full_file_name = os.path.join(COMMUNITY_MODEL_PREFIX,
                                              pretrained_model_name_or_path,
                                              file_name)
                resource_files[file_id] = full_file_name
            resource_files["model_config_file"] = os.path.join(
                COMMUNITY_MODEL_PREFIX, pretrained_model_name_or_path,
                cls.model_config_file)

        default_root = os.path.join(MODEL_HOME, pretrained_model_name_or_path)
        resolved_resource_files = {}
        for file_id, file_path in resource_files.items():
            if file_path is None or os.path.isfile(file_path) or os.path.isfile(file_path.replace('.pdparams', '.pth')):
                file_path = file_path.replace('.pdparams', '.pth') if os.path.isfile(file_path.replace('.pdparams', '.pth')) else file_path
                resolved_resource_files[file_id] = file_path
                continue
            path = os.path.join(default_root, file_path.split('/')[-1])
            if os.path.exists(path) or os.path.exists(path.replace('.pdparams', '.pth')):
                logger.info("Already cached %s" % path)
                resolved_resource_files[file_id] = path
            else:
                logger.info("Downloading %s and saved to %s" %
                            (file_path, default_root))
                try:
                    resolved_resource_files[file_id] = get_path_from_url(
                        file_path, default_root)
                except RuntimeError as err:
                    logger.error(err)
                    raise RuntimeError(
                        f"Can't load weights for '{pretrained_model_name_or_path}'.\n"
                        f"Please make sure that '{pretrained_model_name_or_path}' is:\n"
                        "- a correct model-identifier of built-in pretrained models,\n"
                        "- or a correct model-identifier of community-contributed pretrained models,\n"
                        "- or the correct path to a directory containing relevant modeling files(model_weights and model_config).\n"
                    )

        # Prepare model initialization kwargs
        # Did we saved some inputs and kwargs to reload ?
        model_config_file = resolved_resource_files.pop("model_config_file",
                                                        None)
        if model_config_file is not None:
            with io.open(model_config_file, encoding="utf-8") as f:
                init_kwargs = json.load(f)
        else:
            init_kwargs = init_configuration
        # position args are stored in kwargs, maybe better not include
        init_args = init_kwargs.pop("init_args", ())
        # class name corresponds to this configuration
        init_class = init_kwargs.pop("init_class",
                                     cls.base_model_class.__name__)
        # Check if the loaded config matches the current model class's __init__
        # arguments. If not match, the loaded config is for the base model class.
        if init_class == cls.base_model_class.__name__:
            base_args = init_args
            base_kwargs = init_kwargs
            derived_args = ()
            derived_kwargs = {}
            base_arg_index = None
        else:  # extract config for base model
            derived_args = list(init_args)
            derived_kwargs = init_kwargs
            base_arg = None
            for i, arg in enumerate(init_args):
                if isinstance(arg, dict) and "init_class" in arg:
                    assert arg.pop(
                        "init_class") == cls.base_model_class.__name__, (
                            "pretrained base model should be {}"
                        ).format(cls.base_model_class.__name__)
                    base_arg_index = i
                    base_arg = arg
                    break
            for arg_name, arg in init_kwargs.items():
                if isinstance(arg, dict) and "init_class" in arg:
                    assert arg.pop(
                        "init_class") == cls.base_model_class.__name__, (
                            "pretrained base model should be {}"
                        ).format(cls.base_model_class.__name__)
                    base_arg_index = arg_name
                    base_arg = arg
                    break

            base_args = base_arg.pop("init_args", ())
            base_kwargs = base_arg
        if cls == cls.base_model_class:
            # Update with newly provided args and kwargs for base model
            base_args = base_args if not args else args
            base_kwargs.update(kwargs)
            model = cls(*base_args, **base_kwargs)
        else:
            # Update with newly provided args and kwargs for derived model
            base_parameters_dict = inspect.signature(
                cls.base_model_class.__init__).parameters
            for k, v in kwargs.items():
                if k in base_parameters_dict:
                    base_kwargs[k] = v
            base_model = cls.base_model_class(*base_args, **base_kwargs)
            if base_arg_index is not None:
                derived_args[base_arg_index] = base_model
            else:
                derived_args = (base_model, )  # assume at the first position
            derived_args = derived_args if not args else args
            derived_parameters_dict = inspect.signature(cls.__init__).parameters
            for k, v in kwargs.items():
                if k in derived_parameters_dict:
                    derived_kwargs[k] = v
            model = cls(*derived_args, **derived_kwargs)

        # Maybe need more ways to load resources.
        weight_path = resolved_resource_files["model_state"]
        # assert weight_path.endswith(
        #     ".pdparams"), "suffix of weight must be .pdparams"

        if 'PP-Layout_v1.0_ser_pretrained' in weight_path:
            load_layoutxlm_weights(model, weight_path)
        elif 'PP-Layout_v1.0_re_pretrained' in weight_path:
            load_layoutxlm_weights(model, weight_path)


        # Make sure we are able to load base models as well as derived models
        # (with heads)

        # start_prefix = ""
        # model_to_load = model
        # state_to_load = state_dict
        # unexpected_keys = []
        # missing_keys = []

        # if not hasattr(model, cls.base_model_prefix) and any(
        #         s.startswith(cls.base_model_prefix) for s in state_dict.keys()):
        #     # base model
        #     state_to_load = {}
        #     start_prefix = cls.base_model_prefix + "."
        #     for k, v in state_dict.items():
        #         if k.startswith(cls.base_model_prefix):
        #             state_to_load[k[len(start_prefix):]] = v
        #         else:
        #             unexpected_keys.append(k)
        # if hasattr(model, cls.base_model_prefix) and not any(
        #         s.startswith(cls.base_model_prefix) for s in state_dict.keys()):
        #     # derived model (base model with heads)
        #     model_to_load = getattr(model, cls.base_model_prefix)
        #     for k in model.state_dict().keys():
        #         if not k.startswith(cls.base_model_prefix):
        #             missing_keys.append(k)
        # if len(missing_keys) > 0:
        #     logger.info(
        #         "Weights of {} not initialized from pretrained model: {}".
        #         format(model.__class__.__name__, missing_keys))
        # if len(unexpected_keys) > 0:
        #     logger.info("Weights from pretrained model not used in {}: {}".
        #                 format(model.__class__.__name__, unexpected_keys))
        # if paddle.in_dynamic_mode():
        #     model_to_load.set_state_dict(state_to_load)
        #     return model

        # model_to_load.load_state_dict(state_to_load)

        return model
        # return model, state_to_load

        Creates an instance of `PretrainedModel`. Model weights are loaded
        by specifying name of a built-in pretrained model, or a community contributed model,
        or a local file directory path.

        Args:
            pretrained_model_name_or_path (str): Name of pretrained model or dir path
                to load from. The string can be:

                - Name of a built-in pretrained model
                - Name of a community-contributed pretrained model.
                - Local directory path which contains model weights file("model_state.pdparams")
                  and model config file ("model_config.json").
            *args (tuple): Position arguments for model `__init__`. If provided,
                use these as position argument values for model initialization.
            **kwargs (dict): Keyword arguments for model `__init__`. If provided,
                use these to update pre-defined keyword argument values for model
                initialization. If the keyword is in `__init__` argument names of
                base model, update argument values of the base model; else update
                argument values of derived model.

        Returns:
            PretrainedModel: An instance of `PretrainedModel`.

        Example:
            .. code-block::

                from paddlenlp.transformers import BertForSequenceClassification

                # Name of built-in pretrained model
                model = BertForSequenceClassification.from_pretrained('bert-base-uncased')

                # Name of community-contributed pretrained model
                model = BertForSequenceClassification.from_pretrained('yingyibiao/bert-base-uncased-sst-2-finetuned')

                # Load from local directory path
                model = BertForSequenceClassification.from_pretrained('./my_bert/')
        
ptstructure/vqa/pytorchnlp/transformers/model_utils.py