class_docstr: Cross-covariance loss.
code: def __init__(self, reduce="half_squared_sum"):
      self.y_centered = None
      self.z_centered = None
      self.covariance = None
  
      if reduce not in ("half_squared_sum", "no"):
          raise ValueError(
              "Only 'half_squared_sum' and 'no' are valid "
              "for 'reduce', but '%s' is given" % reduce
          )
      self.reduce = reduce
  
file_path: chainer/chainer/functions/loss/cross_covariance.py
imports: import chainer
  from chainer import backend
  from chainer import function_node
  from chainer import utils
  from chainer.utils import type_check
label_desc: Use image node_id 1 to create a new CrossCovariance object from inherited base classes: function_node with example: obj = CrossCovariance(reduce)