@Override
 protected void performInplaceIntroduce(IntroduceOperation operation) {
   final PsiElement statement = performRefactoring(operation);
   // put caret on identifier after "self."
   if (statement instanceof PyAssignmentStatement) {
     final List<PsiElement> occurrences = operation.getOccurrences();
     final PsiElement occurrence = findOccurrenceUnderCaret(occurrences, operation.getEditor());
     PyTargetExpression target =
         (PyTargetExpression) ((PyAssignmentStatement) statement).getTargets()[0];
     putCaretOnFieldName(operation.getEditor(), occurrence != null ? occurrence : target);
     final InplaceVariableIntroducer<PsiElement> introducer =
         new PyInplaceFieldIntroducer(target, operation, occurrences);
     introducer.performInplaceRefactoring(new LinkedHashSet<>(operation.getSuggestedNames()));
   }
 }