code: def apply_marker(self, marker):
      self.requires(marker.name)
  
imports: import json
  import os
  import sys
  from contextlib import suppress
  import pytest
  from dvc import env
  from dvc.stage import PipelineStage
  from dvc.testing.fixtures import *
  from .dir_helpers import *
  from .remotes import *
  from .scripts import *
label_desc: Use image node_id 3 for calling the DVCTestConfig obj's underlying member method code with example usage: obj.apply_marker(marker) without return types