text: import pytest
  
  from anchore_engine.services.policy_engine.engine.vulns.scanners import GrypeScanner
  
  
  @pytest.mark.parametrize(
      "input, expected_output",
      [
          ("nvd", True),
          ("nvdv2", True),
          (["nvdv2:cves"], True),
          ("", False),
          (["nvd", "test"], False),
          (["test"], False),
      ],
  )
  def test_is_only_nvd_namespace(input, expected_output):
      """
      Tests private function in GrypeScanner that determines if namespace is an nvd namespace
      """
      assert GrypeScanner()._is_only_nvd_namespace(input) is expected_output
  