Return a new picture shape added in its own paragraph at the end of
        the document. The picture contains the image at
        *image_path_or_stream*, scaled based on *width* and *height*. If
        neither width nor height is specified, the picture appears at its
        native size. If only one is specified, it is used to compute
        a scaling factor that is then applied to the unspecified dimension,
        preserving the aspect ratio of the image. The native size of the
        picture is calculated using the dots-per-inch (dpi) value specified
        in the image file, defaulting to 72 dpi if no value is specified, as
        is often the case.

def add_picture(self, image_path_or_stream, width=None, height=None):
        """
        Return a new picture shape added in its own paragraph at the end of
        the document. The picture contains the image at
        *image_path_or_stream*, scaled based on *width* and *height*. If
        neither width nor height is specified, the picture appears at its
        native size. If only one is specified, it is used to compute
        a scaling factor that is then applied to the unspecified dimension,
        preserving the aspect ratio of the image. The native size of the
        picture is calculated using the dots-per-inch (dpi) value specified
        in the image file, defaulting to 72 dpi if no value is specified, as
        is often the case.
        """
        run = self.add_paragraph().add_run()
        return run.add_picture(image_path_or_stream, width, height)