code: def presence():
      """Return a PresenceStage instance."""
      return PresenceStage([])
  
imports: import pytest
  import orion.core
  import orion.core.io.experiment_builder
  import orion.core.utils.backward
  from orion.core.cli.checks.creation import CreationStage
  from orion.core.cli.checks.operations import OperationsStage
  from orion.core.cli.checks.presence import PresenceStage
  from orion.core.io.database.pickleddb import PickledDB
  from orion.core.utils.exceptions import CheckError
label_desc: Use image node_id 2 for calling a global function with example usage: presence() and returns: PresenceStage