code: def forward(
      self, theta: torch.Tensor
  ) -> Tuple[torch.Tensor, torch.Tensor]:
      backcast = theta[:, : self.backcast_size]
      forecast = theta[:, self.backcast_size :]
      forecast = forecast.reshape(len(forecast), -1, self.out_features)
      return backcast, forecast
  
imports: from typing import Tuple, Optional
  import numpy
  import torch
  import torch.nn
  from ..losses.pytorch import MAE
  from ..common._base_windows import BaseWindows
label_desc: Use image node_id 2 for calling the IdentityBasis obj's underlying member method code with example usage: obj.forward(theta) and returns: backcast,  forecast