class_docstr: Test the BackendValidator class.
class_docstr_tok: ["Test","the","BackendValidator","class","."]
code: def teardown_method(self):
      # remove mock missing dependency error for other tests
      del HAS_BACKEND["backend_A"]
      del HAS_BACKEND["backend_B"]
      del HAS_BACKEND["backend_C"]
      del HAS_BACKEND["backend_D"]
      del HAS_BACKEND["backend_E"]
      del ERROR_TYPES["backend_B"]
      del ERROR_TYPES["backend_E"]
      del ERROR_TYPES["backend_D"]
  
imports: import pytest
  from alibi_detect.utils.missing_optional_dependency import ERROR_TYPES
  from alibi_detect.utils.frameworks import BackendValidator, HAS_BACKEND
label_desc: Use image node_id 2 for calling the TestBackendValidator obj's underlying member method code with example usage: obj.teardown_method() without return types