code: def mse(
      x: Tensor,
      y: Tensor,
      norm_dim: Optional[int] = 1,
      mean_dim: Optional[int] = 0,
  ) -> np.ndarray:
      """Compute mean squared error."""
      return _to_numpy_single(
          (torch.norm(x - y, dim=norm_dim) ** 2).mean(dim=mean_dim)
      )
  
file_path: torchsde/diagnostics/utils.py
imports: import itertools
  import os
  import random
  import matplotlib.pyplot
  import numpy
  import torch
  from scipy import stats
  from torchsde.types import Optional, Tensor, Sequence, Union, Callable
label_desc: Use image node_id 3 for calling a global function with example usage: mse(x, y, norm_dim, mean_dim) and returns: _to_numpy_single