Sorry, yes, you are right — that is not an error, yes.
That just a warning, and only if verbose mode turned on.
Regarding a typo — that is passed by tests, since
from collection import Mapping
still works, but throws a warning.
I use dockerized Tryton.
$ docker exec -it -u root tryton bash -c "trytond-admin -d tryton -c /etc/trytond.conf -vv" | grep -v INFO
67 139980340995904 [2020-12-16 07:36:00,793] WARNING py.warnings /usr/lib/python3/dist-packages/ldap3/utils/ciDict.py:30: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
67 139980340995904 [2020-12-16 07:36:01,666] WARNING py.warnings /usr/local/lib/python3.7/dist-packages/elasticsearch/compat.py:38: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
from collections import Mapping
67 139980340995904 [2020-12-16 07:36:01,693] WARNING py.warnings /usr/lib/python3.7/importlib/_bootstrap.py:219: ImportWarning: can't resolve package from __spec__ or __package__, falling back on __name__ and __path__
return f(*args, **kwds)