cannot import name 'X' from namespace 'A.B.C' (unknown location) #2116

I am trying to import a class from the known and properly spelled namespace from the loaded assembly.

I am loading a bunch of assemblies belonging to the same library (they are loaded OK as I can check by the AddReference return)
clr.AddReference("SCT.Common") clr.AddReference("SCT.Common.35") clr.AddReference("SCT.Common.40") clr.AddReference("SCT.IO") clr.AddReference("SCT.IO.35") clr.AddReference("SCT.IO.40")

As a test I am calling another known class:
from SCT.Instrumentation import ContextInstrumentation as ci appDomainInfo = ci.DumpAppDomainInfo() print(appDomainInfo)

Imports OK, runs OK, returns printable result.

Then I am loading another class:
from SCT.IO.TemplateParser import TemplateBuilder as tb

This time around I am getting an error:
Traceback (most recent call last): File "D:\_WorkRoot\Tests\...\sctlib.py", line 35, in <module> from SCT.IO.TemplateParser import TemplateBuilder as tb ImportError: cannot import name 'TemplateBuilder' from 'SCT.IO.TemplateParser' (unknown location)

Context:
0) Python 3.10 PythonNet 3.0.1

1. I am using assembly names inside AddRreference calls
2. SCT.Instrumentation is a namespace with classes defined in SCT.Common, SCT.Common.35 and SCT.Common.40 assemblies. The specific module I am using is defined in the the first referenced assembly.
3. SCT.IO is a namespace with classes defined in all 6 assemblies. The namespace SCT.IO.TemplateParser is defined in the very last referenced assembly ("SCT.IO.40")
4. SCT.IO.40 has a target framework as .Net Framework 4.8. But I can see successful reference:

asmSCTIO40 = clr.AddReference("SCT.IO.40") print(asmSCTIO40)
"SCT.IO.40, Version=400.2023.201.25619, Culture=neutral, PublicKeyToken=null"

I noticed few discussion on StackOverflow - it seems I am following everything I have to.