code: def pytest_generate_tests(metafunc):
      str_revs = metafunc.config.getoption("--dvc-revs")
      revs = str_revs.split(",") if str_revs else [None]
      if "dvc_rev" in metafunc.fixturenames:
          metafunc.parametrize("dvc_rev", revs, scope="session")
  
label_desc: Use image node_id 2 for calling a global function with example usage: pytest_generate_tests(metafunc) without return types