Cannot import open3d packages(.io , .ml , .t ) into the python script after installation.

### 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](https://www.open3d.org/docs/latest/getting_started.html#development-version-pip).
- [X] I have checked the [release documentation](https://www.open3d.org/docs/release/) and the [latest documentation](https://www.open3d.org/docs/latest/) (for `main` branch).

### Steps to reproduce the issue

#### I installed the Python package wheel version from the website:
```
pip install https://storage.googleapis.com/open3d-releases/python-wheels/open3d-0.18.0+0cf605f-cp38-cp38-manylinux_2_27_x86_64.whl
```

#### Then, I am importing the open3D in the vscode :
```python
from open3D import io
#.....
io.read_point_cloud() ## its not available in the .venv/python3.8/site-packages
```

### Error message

```shell
NA : only that I am not able to find the api's for the given functions as described in the documentation.
```

### Open3D, Python and System information

```markdown
- Operating system: Ubuntu 20.04
- Python version: Python 3.8.10
- Open3D version: output from python: 0.18.0
- System architecture: x86
- Is this a remote workstation?: yes
- How did you install Open3D?: pip
- Compiler version (if built from source): gcc 9.4.0
```

### Additional information

_No response_