Enable dragging of a QT5 QGraphicsView with middle mouse button (or any other button than the default)

MyGraphicsView.cpp

/**
    So you want to use the QGraphicsView Drag Mode but with another mouse button than the default left click?
    You can of course reimplement the mouse_move_event in a subclass but did you notice how ugly it is to implement
    all the dragging functionality by yourself?
    
    All you want to do is use another mouse_button with the existing dragging functionality 
    but there is no such thing as a setDraggingButton function.
    
    Here we use a little hack which enables the dragging mode only temporarly when clicking a button of your choice and then
    sends a left-click event which will trigger the standard dragging functionality of the QGraphicsView.
    
    Keywords: QT5, Dragging, QGraphicsView
**/

class MyGraphicsView : public QGraphicsView {
	Q_OBJECT
  
  bool eventFilter(QObject* object, QEvent* event);
   
};

bool MyGraphicsView::eventFilter(QObject *object, QEvent *event) {
 
  if (event->type() == QEvent::MouseButtonPress)
  {
      QMouseEvent* mouse_event = static_cast<QMouseEvent*>(event);
      // Enter here any button you like
	  if (mouse_event->button() == Qt::MiddleButton)
	  {
          // temporarly enable dragging mode
		  this->setDragMode(QGraphicsView::DragMode::ScrollHandDrag);
          // emit a left mouse click (the default button for the drag mode)
		  QMouseEvent* pressEvent = new QMouseEvent(QEvent::GraphicsSceneMousePress, 
                                    mouse_event->pos(), Qt::MouseButton::LeftButton,
                                    Qt::MouseButton::LeftButton, Qt::KeyboardModifier::NoModifier);
          
		  this->mousePressEvent(pressEvent);
	  }
      else if (event->type() == QEvent::MouseButtonRelease)
	  {
          // disable drag mode if dragging is finished
		  this->setDragMode(QGraphicsView::DragMode::NoDrag);
	  }
      
      Q_UNUSED(object)
	  return false;
}

also working in pyqt. Just add installEventFilter on the both QGraphicsView and QGraphicsScene