docs: def delta_decode(data, axis=-1, out=None):
      """Decode Delta."""
      if out is not None and not out.flags.writeable:
          out = None
      if isinstance(data, (bytes, bytearray)):
          data = numpy.frombuffer(data, dtype='u1')
          return numpy.cumsum(data, axis=0, dtype='u1', out=out).tobytes()
      if data.dtype.kind == 'f':
          view = data.view('u%i' % data.dtype.itemsize)
          view = numpy.cumsum(view, axis=axis, dtype=view.dtype)
          return view.view(data.dtype)
      return numpy.cumsum(data, axis=axis, dtype=data.dtype, out=out)