'Return the current shape polygon as tuple of coordinate pairs.
No argument.
Examples (for a Turtle instance named turtle):
>>> turtle.shape("square")
>>> turtle.shapetransform(4, -1, 0, 2)
>>> turtle.get_shapepoly()
((50, -20), (30, 20), (-50, 20), (-30, -20))'

def get_shapepoly(self):

    shape = self.screen._shapes[self.turtle.shapeIndex]
    if (shape._type == 'polygon'):
        return self._getshapepoly(shape._data, (shape._type == 'compound'))
