code: def forward_transfer_metrics(
      *, experience=False, stream=False
  ) -> List[PluginMetric]:
      """
      Helper method that can be used to obtain the desired set of
      plugin metrics.
  
      :param experience: If True, will return a metric able to log
          the forward transfer on each evaluation experience.
      :param stream: If True, will return a metric able to log
          the forward transfer averaged over the evaluation stream experiences,
          which have been observed during training.
  
      :return: A list of plugin metrics.
      """
  
      metrics: List[PluginMetric] = []
  
      if experience:
          metrics.append(ExperienceForwardTransfer())
  
      if stream:
          metrics.append(StreamForwardTransfer())
  
      return metrics
  
imports: from abc import ABC, abstractmethod
  from typing import Dict, TYPE_CHECKING, Generic, List, Optional, TypeVar, Union
  from avalanche.evaluation.metric_definitions import Metric, PluginMetric
  from avalanche.evaluation.metric_results import MetricValue, MetricResult
  from avalanche.evaluation.metrics import TaskAwareAccuracy, Mean
  from avalanche.evaluation.metric_utils import get_metric_name, phase_and_task, stream_type
label_desc: Use image node_id 1 for calling a global function with example usage: forward_transfer_metrics() and returns: metrics