Return a newly appended `p:pic` element as specified.

        The `p:pic` element displays the image in *image_part* with size and
        position specified by *x*, *y*, *cx*, and *cy*. The element is
        appended to the shape tree, causing it to be displayed first in
        z-order on the slide.

def _add_pic_from_image_part(self, image_part, rId, x, y, cx, cy):
        """Return a newly appended `p:pic` element as specified.

        The `p:pic` element displays the image in *image_part* with size and
        position specified by *x*, *y*, *cx*, and *cy*. The element is
        appended to the shape tree, causing it to be displayed first in
        z-order on the slide.
        """
        id_ = self._next_shape_id
        scaled_cx, scaled_cy = image_part.scale(cx, cy)
        name = 'Picture %d' % (id_-1)
        desc = image_part.desc
        pic = self._grpSp.add_pic(
            id_, name, desc, rId, x, y, scaled_cx, scaled_cy
        )
        return pic