message: Use fmt.Errorf() instead of bug()
diff: @@ -213,7 +213,7 @@ func (t *Tensor) Reshape(new_shape []int64) error {
  new_shape_size := numElements(new_shape)
  if old_shape_size != new_shape_size {
  - return bug("unable to convert shape %v (num_elements: %d) into shape %v (num_elements: %d)", t.shape, old_shape_size, new_shape, new_shape_size)
  + return fmt.Errorf("unable to convert shape %v (num_elements: %d) into shape %v (num_elements: %d)", t.shape, old_shape_size, new_shape, new_shape_size)
  }
  if len(new_shape) == 0 {
  