'Add a rotation (in degrees) around the point (x, y) in place.
Returns *self*, so this method can easily be chained with more
calls to :meth:`rotate`, :meth:`rotate_deg`, :meth:`translate`
and :meth:`scale`.'

def rotate_deg_around(self, x, y, degrees):

    (x, y) = (float(x), float(y))
    return self.translate((- x), (- y)).rotate_deg(degrees).translate(x, y)
