From: królewna on
I have found the solution. I dont know why in python documentation there
is not a single word about this option. I've found it in pysqlite doc
site. So we have to add a new keyword argument to connection function
and we will be able to create cursors out of it in different thread. So use:

sqlite.connect(":memory:", check_same_thread = False)

works out perfectly for me. Of course from now on me need to take care
of safe multithreading access to the db. Anyway thx all for trying to help.

best regards