from open3d import t works but "No module named 'open3d.t'"

[Zador-Pataki]

Hi, I encountered something I have not yet experienced in python.

Following python script is executed:

from open3d import t
import open3d.t as whatever

with output:
ModuleNotFoundError: No module named 'open3d.t'

Can you explain how this is possible? Why can we import t form open3d but can not import open3d.t?