code: def __init__(self, revs: Collection[str]):
      rev_str = ",".join(revs)
      super().__init__(
          f"Task '{rev_str}' is initializing, please wait a few seconds "
          "until the experiments start running to retry the kill operation."
      )
  
imports: from typing import Collection
  from dvc.exceptions import DvcException
label_desc: Use image node_id 1 to create a new CannotKillTasksError object from inherited base classes: DvcException with example: obj = CannotKillTasksError(revs)