code: def get_data(self):
          
          return ffi.buffer(
              cairo.cairo_image_surface_get_data(self._pointer),
              self.get_stride() * self.get_height())
docs: Return the buffer pointing to the image’s pixel data,
          encoded according to the surface’s :ref:`FORMAT` string.
  
          A call to :meth:`flush` is required before accessing the pixel data
          to ensure that all pending drawing operations are finished.
          A call to :meth:`~Surface.mark_dirty` is required
          after the data is modified.
  
          :returns: A read-write CFFI buffer object.