'Add a new scale+rotation handle to the ROI. When dragging a handle of
this type, the user can simultaneously rotate the ROI around an
arbitrary center point as well as scale the ROI by dragging the handle
toward or away from the center point.
**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
scaling and rotation take 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 addScaleRotateHandle(self, pos, center, item=None, name=None, index=None):

    pos = Point(pos)
    center = Point(center)
    if ((pos[0] != center[0]) and (pos[1] != center[1])):
        raise Exception('Scale/rotate    handles    must    have    either    the    same    x    or    y    coordinate    as    their    center    point.')
    return self.addHandle({'name': name, 'type': 'sr', 'center': center, 'pos': pos, 'item': item}, index=index)
