def forward(
        self,
        past_values: torch.Tensor,
        past_time_features: torch.Tensor,
        past_observed_mask: torch.Tensor,
        static_categorical_features: Optional[torch.Tensor] = None,
        static_real_features: Optional[torch.Tensor] = None,
        future_values: Optional[torch.Tensor] = None,
        future_time_features: Optional[torch.Tensor] = None,
        future_observed_mask: Optional[torch.Tensor] = None,
        decoder_attention_mask: Optional[torch.LongTensor] = None,
        head_mask: Optional[torch.Tensor] = None,
        decoder_head_mask: Optional[torch.Tensor] = None,
        cross_attn_head_mask: Optional[torch.Tensor] = None,
        encoder_outputs: Optional[List[torch.FloatTensor]] = None,
        past_key_values: Optional[List[torch.FloatTensor]] = None,
        output_hidden_states: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        use_cache: Optional[bool] = None,
        return_dict: Optional[bool] = None,
    ) -> Union[Seq2SeqTSModelOutput, Tuple]:
        r"""
        Returns:

        Examples:

        ```python
        >>> from huggingface_hub import hf_hub_download
        >>> import torch
        >>> from transformers import InformerForPrediction

        >>> file = hf_hub_download(
        ...     repo_id="hf-internal-testing/tourism-monthly-batch", filename="train-batch.pt", repo_type="dataset"
        ... )
        >>> batch = torch.load(file)

        >>> model = InformerForPrediction.from_pretrained("huggingface/informer-tourism-monthly")

        >>> # during training, one provides both past and future values
        >>> # as well as possible additional features
        >>> outputs = model(
        ...     past_values=batch["past_values"],
        ...     past_time_features=batch["past_time_features"],
        ...     past_observed_mask=batch["past_observed_mask"],
        ...     static_categorical_features=batch["static_categorical_features"],
        ...     static_real_features=batch["static_real_features"],
        ...     future_values=batch["future_values"],
        ...     future_time_features=batch["future_time_features"],
        ... )

        >>> loss = outputs.loss
        >>> loss.backward()

        >>> # during inference, one only provides past values
        >>> # as well as possible additional features
        >>> # the model autoregressively generates future values
        >>> outputs = model.generate(
        ...     past_values=batch["past_values"],
        ...     past_time_features=batch["past_time_features"],
        ...     past_observed_mask=batch["past_observed_mask"],
        ...     static_categorical_features=batch["static_categorical_features"],
        ...     static_real_features=batch["static_real_features"],
        ...     future_time_features=batch["future_time_features"],
        ... )

        >>> mean_prediction = outputs.sequences.mean(dim=1)
        ```"""

        return_dict = return_dict if return_dict is not None else self.config.use_return_dict
        if future_values is not None:
            use_cache = False

        outputs = self.model(
            past_values=past_values,
            past_time_features=past_time_features,
            past_observed_mask=past_observed_mask,
            static_categorical_features=static_categorical_features,
            static_real_features=static_real_features,
            future_values=future_values,
            future_time_features=future_time_features,
            decoder_attention_mask=decoder_attention_mask,
            head_mask=head_mask,
            decoder_head_mask=decoder_head_mask,
            cross_attn_head_mask=cross_attn_head_mask,
            encoder_outputs=encoder_outputs,
            past_key_values=past_key_values,
            output_hidden_states=output_hidden_states,
            output_attentions=output_attentions,
            use_cache=use_cache,
            return_dict=return_dict,
        )

        prediction_loss = None
        params = None
        if future_values is not None:
            params = self.output_params(outputs[0])  # outputs.last_hidden_state
            # loc is 3rd last and scale is 2nd last output
            distribution = self.output_distribution(params, loc=outputs[-3], scale=outputs[-2])

            loss = self.loss(distribution, future_values)

            if future_observed_mask is None:
                future_observed_mask = torch.ones_like(future_values)

            if len(self.target_shape) == 0:
                loss_weights = future_observed_mask
            else:
                loss_weights, _ = future_observed_mask.min(dim=-1, keepdim=False)

            prediction_loss = weighted_average(loss, weights=loss_weights)

        if not return_dict:
            outputs = ((params,) + outputs[1:]) if params is not None else outputs[1:]
            return ((prediction_loss,) + outputs) if prediction_loss is not None else outputs

        return Seq2SeqTSPredictionOutput(
            loss=prediction_loss,
            params=params,
            past_key_values=outputs.past_key_values,
            decoder_hidden_states=outputs.decoder_hidden_states,
            decoder_attentions=outputs.decoder_attentions,
            cross_attentions=outputs.cross_attentions,
            encoder_last_hidden_state=outputs.encoder_last_hidden_state,
            encoder_hidden_states=outputs.encoder_hidden_states,
            encoder_attentions=outputs.encoder_attentions,
            loc=outputs.loc,
            scale=outputs.scale,
            static_features=outputs.static_features,
        )

        Returns:

        Examples:

        ```python
        >>> from huggingface_hub import hf_hub_download
        >>> import torch
        >>> from transformers import InformerForPrediction

        >>> file = hf_hub_download(
        ...     repo_id="hf-internal-testing/tourism-monthly-batch", filename="train-batch.pt", repo_type="dataset"
        ... )
        >>> batch = torch.load(file)

        >>> model = InformerForPrediction.from_pretrained("huggingface/informer-tourism-monthly")

        >>> # during training, one provides both past and future values
        >>> # as well as possible additional features
        >>> outputs = model(
        ...     past_values=batch["past_values"],
        ...     past_time_features=batch["past_time_features"],
        ...     past_observed_mask=batch["past_observed_mask"],
        ...     static_categorical_features=batch["static_categorical_features"],
        ...     static_real_features=batch["static_real_features"],
        ...     future_values=batch["future_values"],
        ...     future_time_features=batch["future_time_features"],
        ... )

        >>> loss = outputs.loss
        >>> loss.backward()

        >>> # during inference, one only provides past values
        >>> # as well as possible additional features
        >>> # the model autoregressively generates future values
        >>> outputs = model.generate(
        ...     past_values=batch["past_values"],
        ...     past_time_features=batch["past_time_features"],
        ...     past_observed_mask=batch["past_observed_mask"],
        ...     static_categorical_features=batch["static_categorical_features"],
        ...     static_real_features=batch["static_real_features"],
        ...     future_time_features=batch["future_time_features"],
        ... )

        >>> mean_prediction = outputs.sequences.mean(dim=1)
        ```
dpkd/transformers/src/transformers/models/informer/modeling_informer.py