Get the values for the SHAPE record.

def _get_struct_shape(self):
        """Get the values for the SHAPE record."""
        obj = _make_object("Shape")
        bc = BitConsumer(self._src)
        obj.NumFillBits = n_fill_bits = bc.u_get(4)
        obj.NumLineBits = n_line_bits = bc.u_get(4)
        obj.ShapeRecords = self._get_shaperecords(
            n_fill_bits, n_line_bits, 0)
        return obj