Align camera to obj when offscreen rendering

### Checklist

- [X] I have searched for [similar issues](https://github.com/isl-org/Open3D/issues).
- [X] For Python issues, I have tested with the [latest development wheel](http://www.open3d.org/docs/latest/getting_started.html#development-version-pip).
- [X] I have checked the [release documentation](http://www.open3d.org/docs/release/) and the [latest documentation](http://www.open3d.org/docs/latest/) (for `master` branch).

### My Question

I want to find the proper position of camera when render 3d model to image. So I tried the following to visualize the view for getting camera info. But when run this, it came error when add_geometry. Does someone can help this, or have a better way to find the camera position when rendering the image, thanks a lot!

```

box = o3d.io.read_triangle_model("D:\\blender_model\\1x1.obj")

vis = o3d.visualization.Visualizer()
vis.create_window()
vis.add_geometry(box)
vis.run()
vis.destroy_window()

```

Error msg:
TypeError: add_geometry(): incompatible function arguments. The following argument types are supported:
1. (self: open3d.cpu.pybind.visualization.Visualizer, geometry: open3d.cpu.pybind.geometry.Geometry, reset_bounding_box: bool = True) -> bool

Invoked with: Visualizer with name Open3D,