class_docstr: Reduce dimensions using PCA.
  
  This nn.Modue subclass reduces the dimensions of the inputs
  specified by `n_components`.
  
  The input is a 2-dimensional `Tensor` of size `batch` x `features`,
  the output is a `Tensor` of size `batch` x `n_components`.
code: def forward(self, x: torch.Tensor) -> torch.Tensor:
      x = x - self.mean
      reduced = x @ self.comp
      return reduced
  
file_path: TorchDrift/torchdrift/reducers/pca.py
imports: import torch
  from .None import Reducer
  import torchdrift.utils
label_desc: Use image node_id 4 for calling the PCAReducer obj's underlying member method code with example usage: obj.forward(x) and returns: reduced