Reference cycle in QGraphicsScene causes SIGSEGV

I like the QGraphicsScene feature, but I've run into a problem.

I'm trying to create items to add to a QGraphicsScene, and I want them to respond to hover events. I made them raise events back to the main widget that owns the QGraphicsScene, but I suspect that reference cycle is causing problems.

I don't see any problems when I run the main program, but I do see it when I run a bunch of unit tests that are creating widgets and tearing them down, so I guess either there's a bug in the reference handling, or I'm missing a clean up step.

Here's an example script that reproduces the SIGSEGV by repeatedly creating and releasing a widget with a QGraphicsScene.

from PySide2.QtWidgets import QApplication, QWidget, QVBoxLayout, \
    QGraphicsView, QGraphicsScene, QGraphicsEllipseItem


class MyDisplay(QWidget):
    def __init__(self):
        super().__init__()
        layout = QVBoxLayout(self)
        self.view = view = QGraphicsView()
        layout.addWidget(view)
        scene = QGraphicsScene(0, 0, 200, 200)
        view.setScene(scene)
        piece = QGraphicsEllipseItem(0, 0, 100, 100)
        piece.foo = self
        scene.addItem(piece)


def main():
    app = QApplication()
    n = 100  # Anything higher than 21 triggers a SIGSEGV on my laptop.
    is_tidy = False  # False triggers SIGSEGV, True doesn't.
    for i in range(n):
        display = MyDisplay()
        if is_tidy:
            display.view.scene().clear()



main()

If I don't explicitly clear the QGraphicsScene, I get the SIGSEGV. I don't see anything in the QGraphicsScene documentation that says I have to call clear(), though. Is that really needed, or is this a bug?