void (final @NotNull PyReferenceExpression node) { if (myPositive && (isIfReferenceStatement(node) || isIfReferenceConditionalStatement(node) || isIfNotReferenceStatement(node))) { // we could not suggest `None` because it could be a reference to an empty collection // so we could push only non-`None` assertions pushAssertion(node, !myPositive, false, context -> PyNoneType.INSTANCE, null); return; } super.visitPyReferenceExpression(node); }