Is there something wrong in of icet?

Look at the following code from the head of, icet v2.1

This module provides the Structure class.
from typing import List, Sequence
from ase import Atom, Atoms

from _icet import _Structure
from .lattice_site import LatticeSite

class Structure(_Structure):

_icet is a library written in c++ that includes the definition of class Structure rather than _Structure. If you try simply by “from _icet import _Structure”. python interpreter just reports error since it cannot find where _Structure is.