@Override
  public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
    final PsiElement element = descriptor.getPsiElement();
    final PyElementGenerator elementGenerator = PyElementGenerator.getInstance(project);
    final PyNamedParameter parameter = elementGenerator.createParameter(element.getText() + "=None");
    final PyFunction function = PsiTreeUtil.getParentOfType(element, PyFunction.class);
    if (function != null) {
      final PyParameterList parameterList = function.getParameterList();
      parameterList.addParameter(parameter);
      CodeInsightUtilCore.forcePsiPostprocessAndRestoreElement(parameterList);
      final TemplateBuilder builder = TemplateBuilderFactory.getInstance().createTemplateBuilder(parameter);
      builder.replaceRange(TextRange.create(parameter.getTextLength() - 4, parameter.getTextLength()), "None");
      PythonTemplateRunner.runTemplate(function.getContainingFile(), builder);
    }
  }
@Override
  public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor)