'Add a new rotation handle to the ROI. Dragging a rotation handle allows
the user to change the angle of the ROI.
**Arguments**
pos                 (length-2 sequence) The position of the handle
relative to the shape of the ROI. A value of (0,0)
indicates the origin, whereas (1, 1) indicates the
upper-right corner, regardless of the ROI\'s size.
center              (length-2 sequence) The center point around which
rotation takes place.
item                The Handle instance to add. If None, a new handle
will be created.
name                The name of this handle (optional). Handles are
identified by name when calling
getLocalHandlePositions and getSceneHandlePositions.'

def addRotateHandle(self, pos, center, item=None, name=None, index=None):

    pos = Point(pos)
    center = Point(center)
    return self.addHandle({'name': name, 'type': 'r', 'center': center, 'pos': pos, 'item': item}, index=index)
