class_docstr: Mother class for all multi-output regression metrics.
class_docstr_tok: ["Mother","class","for","all","multi-output","regression","metrics","."]
docstr: Update the metric.
docstr_tok: ["Update","the","metric","."]
code: def update(
      self,
      y_true: dict[str | int, float | int],
      y_pred: dict[str | int, float | int],
  ):
      """Update the metric."""
  
imports: from __future__ import annotations
  import abc
  from river import base, utils
  from river.metrics.base import Metric
  from .confusion import MultiLabelConfusionMatrix
label_desc: Use image node_id 1 for calling the MultiOutputRegressionMetric obj's underlying member method code with example usage: obj.update(y_true, y_pred) without return types