code: def mean_squared_error(x0, x1):
      """Mean squared error function.
  
      The function computes the mean squared error between two variables. The
      mean is taken over the minibatch. Args ``x0`` and ``x1`` must have the
      same dimensions. Note that the error is not scaled by 1/2.
  
      Args:
          x0 (:class:`~chainer.Variable` or :ref:`ndarray`): Input variable.
          x1 (:class:`~chainer.Variable` or :ref:`ndarray`): Input variable.
  
      Returns:
          ~chainer.Variable:
              A variable holding an array representing the mean squared
              error of two inputs.
  
       .. admonition:: Example
  
          1D array examples:
  
          >>> x = np.array([1, 2, 3, 4]).astype(np.float32)
          >>> y = np.array([0, 0, 0, 0]).astype(np.float32)
          >>> F.mean_squared_error(x, y)
          variable(7.5)
          >>> x = np.array([1, 2, 3, 4, 5, 6]).astype(np.float32)
          >>> y = np.array([7, 8, 9, 10, 11, 12]).astype(np.float32)
          >>> F.mean_squared_error(x, y)
          variable(36.)
  
          2D array example:
  
          In this example, there are 4 elements, and thus 4 errors
          >>> x = np.array([[1, 2], [3, 4]]).astype(np.float32)
          >>> y = np.array([[8, 8], [8, 8]]).astype(np.float32)
          >>> F.mean_squared_error(x, y)
          variable(31.5)
  
          3D array example:
  
          In this example, there are 8 elements, and thus 8 errors
          >>> x = np.reshape(np.array([1, 2, 3, 4, 5, 6, 7, 8]), (2, 2, 2))
          >>> y = np.reshape(np.array([8, 8, 8, 8, 8, 8, 8, 8]), (2, 2, 2))
          >>> x = x.astype(np.float32)
          >>> y = y.astype(np.float32)
          >>> F.mean_squared_error(x, y)
          variable(17.5)
  
      """
      return MeanSquaredError().apply((x0, x1))[0]
  
file_path: chainer/chainer/functions/loss/mean_squared_error.py
imports: import numpy
  from chainer import function_node
  import chainer.functions
  from chainer.utils import type_check
label_desc: Use image node_id 1 for calling a global function with example usage: mean_squared_error(x0, x1) and returns: MeanSquaredError