 year", "day of the month", etc. encoded as vectors (for instance as Fourier features). These
            could also be so-called "age" features, which basically help the model know "at which point in life" a
            time-series is. Age features have small values for distant past time steps and increase monotonically the
            more we approach the current time step. Holiday features are also a good example of time features.

            These features serve as the "positional encodings" of the inputs. So contrary to a model like BERT, where
            the position encodings are learned from scratch internally as parameters of the model, the Time Series
            Transformer requires to provide additional time features. The Time Series Transformer only learns
            additional embeddings for `static_categorical_features`.

            Additional dynamic real covariates can be concatenated to this tensor, with the caveat that these features
            must but known at prediction time.

            The `num_features` here is equal to `config.`num_time_features` + `config.num_dynamic_real_features`.
        past_observed_mask (`torch.BoolTensor` of shape `(batch_size, sequence_length)` or `(batch_size, sequence_length, input_size)`, *optional*):
            Boolean mask to indicate which `past_values` were observed and which were missing. Mask values selected in
            `[0, 1]`:

            - 1 for values that are **observed**,
            - 0 for values that are **missing** (i.e. NaNs that were replaced by zeros).

        static_categorical_features (`torch.LongTensor` of shape `(batch_size, number of static categorical features)`, *optional*):
            Optional static categorical features for which the model will learn an embedding, which it will add to the
            values of the time series.

            Static categorical features are features which have the same value for all time steps (static over time).

            A typical example of a static categorical feature is a time series ID.
        static_real_features (`torch.FloatTensor` of shape `(batch_size, number of static real features)`, *optional*):
            Optional static real features which the model will add to the values of the time series.

            Static real features are features which have the same value for all time steps (static over time).

            A typical example of a static real feature is promotion information.
        future_values (`torch.FloatTensor` of shape `(batch_size, prediction_length)` or `(batch_size, prediction_length, input_size)`, *optional*):
            Future values of the time series, that serve as labels for the model. The `future_values` is what the
            Transformer needs during training to learn to output, given the `past_values`.

            The sequence length here is equal to `prediction_length`.

            See the demo notebook and code snippets for details.

            Optionally, during training any missing values need to be replaced with zeros and indicated via the
            `future_observed_mask`.

            For multivariate time series, the `input_size` > 1 dimension is required and corresponds to the number of
            variates in the time series per time step.
        future_time_features (`torch.FloatTensor` of shape `(batch_size, prediction_length, num_features)`):
            Required time features for the prediction window, which the model internally will add to `future_values`.
            These could be things like "month of year", "day of the month", etc. encoded as vectors (for instance as
            Fourier features). These could also be so-called "age" features, which basically help the model know "at
            which point in life" a time-series is. Age features have small values for distant past time steps and
            increase monotonically the more we approach the current time step. Holiday features are also a good example
            of time features.

            These features serve as the "positional encodings" of the inputs. So contrary to a model like BERT, where
            the position encodings are learned from scratch internally as parameters of the model, the Time Series
            Transformer requires to provide additional time features. The Time Series Transformer only learns
            additional embeddings for `static_categorical_features`.

            Additional dynamic real covariates can be concatenated to this tensor, with the caveat that these features
            must but known at prediction time.

            The `num_features` here is equal to `config.`num_time_features` + `config.num_dynamic_real_features`.
        future_observed_mask (`torch.BoolTensor` of shape `(batch_size, sequence_length)` or `(batch_size, sequence_length, input_size)`, *optional*):
            Boolean mask to indicate which `future_values` were observed and which were missing. Mask values selected
            in `[0, 1]`:

            - 1 for values that are **observed**,
            - 0 for values that are **missing** (i.e. NaNs that were replaced by zeros).

            This mask is used to filter out missing values for the final loss calculation.
        attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
            Mask to avoid performing attention on certain token indices. Mask values selected in `[0, 1]`:

            - 1 for tokens that are **not masked**,
            - 0 for tokens that are **masked**.

            [What are attention masks?](../glossary#attention-mask)
        decoder_attention_mask (`torch.LongTensor` of shape `(batch_size, target_sequence_length)`, *optional*):
            Mask to avoid performing attention on certain token indices. By default, a causal mask will be used, to
            make sure the model can only look at previous inputs in order to predict the future.
        head_mask (`torch.Tensor` of shape `(encoder_layers, encoder_attention_heads)`, *optional*):
            Mask to nullify selected heads of the attention modules in the encoder. Mask values selected in `[0, 1]`:

            - 1 indicates the head is **not masked**,
            - 0 indicates the head is **masked**.

        decoder_head_mask (`torch.Tensor` of shape `(decoder_layers, decoder_attention_heads)`, *optional*):
            Mask to nullify selected heads of the attention modules in the decoder. Mask values selected in `[0, 1]`:

            - 1 indicates the head is **not masked**,
            - 0 indicates the head is **masked**.

        cross_attn_head_mask (`torch.Tensor` of shape `(decoder_layers, decoder_attention_heads)`, *optional*):
            Mask to nullify selected heads of the cross-attention modules. Mask values selected in `[0, 1]`:

            - 1 indicates the head is **not masked**,
            - 0 indicates the head is **masked**.

        encoder_outputs (`tuple(tuple(torch.FloatTensor)`, *optional*):
            Tuple consists of `last_hidden_state`, `hidden_states` (*optional*) and `attentions` (*optional*)
            `last_hidden_state` of shape `(batch_size, sequence_length, hidden_size)` (*optional*) is a sequence of
            hidden-states at the output of the last layer of the encoder. Used in the cross-attention of the decoder.
        past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
            Tuple of `tuple(torch.FloatTensor)` of length `config.n_layers`, with each tuple having 2 tensors of shape
            `(batch_size, num_heads, sequence_length, embed_size_per_head)`) and 2 additional tensors of shape
            `(batch_size, num_heads, encoder_sequence_length, embed_size_per_head)`.

            Contains pre-computed hidden-states (key and values in the self-attention blocks and in the cross-attention
            blocks) that can be used (see `past_key_values` input) to speed up sequential decoding.

            If `past_key_values` are used, the user can optionally input only the last `decoder_input_ids` (those that
            don't have their past key value states given to this model) of shape `(batch_size, 1)` instead of all
            `decoder_input_ids` of shape `(batch_size, sequence_length)`.
        inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`, *optional*):
            Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This
            is useful if you want more control over how to convert `input_ids` indices into associated vectors than the
            model's internal embedding lookup matrix.
        use_cache (`bool`, *optional*):
            If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see
            `past_key_values`).
        output_attentions (`bool`, *optional*):
            Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned
            tensors for more detail.
        output_hidden_states (`bool`, *optional*):
            Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for
            more detail.
        return_dict (`bool`, *optional*):
            Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
c