text: import torch
  import torch.nn.functional as F
  
  
  def nll_loss(output: torch.tensor, target: torch.tensor):
      return F.nll_loss(output, target)
  
  
  def cse(output: torch.tensor, target: torch.tensor):
      """
      Using the pytorch cross entropy loss means that you don't have to add a
      softmax activation.
  
      """
      return F.cross_entropy(output, target)
  
  
  def mse(output: torch.tensor, target: torch.tensor):
      return F.mse_loss(output, target)
  