Reimplemented to emit zoom in/out signals when Ctrl is pressed

def wheelEvent(self, event):
        """Reimplemented to emit zoom in/out signals when Ctrl is pressed"""
        # This feature is disabled on MacOS, see Issue 1510
        if sys.platform != 'darwin':
            if event.modifiers() & Qt.ControlModifier:
                if hasattr(event, 'angleDelta'):
                    if event.angleDelta().y() < 0:
                        self.zoom_out.emit()
                    elif event.angleDelta().y() > 0:
                        self.zoom_in.emit()
                elif hasattr(event, 'delta'):
                    if event.delta() < 0:
                        self.zoom_out.emit()
                    elif event.delta() > 0:
                        self.zoom_in.emit()
                return
        QPlainTextEdit.wheelEvent(self, event)
        self.highlight_current_cell()