Tested with:
from datetime import datetime, timedelta
from dateutil.relativedelta import relativedelta
n = datetime.now()
assert n + timedelta(days=365) == n + relativedelta(years=1)
Fix 'module' object is not callable
* rhn_register: fix Python 3 compatibility
* rhn_register: update requirements
* rhn_register: add unit tests
* Add missing method name
* use a dedicated line for XML related requirements
* rhn_register: drop support for Python 2.4
* rhn_register unit tests: fix Python 3 compatibility
* refactor in order to check order of the requests
* Revert change to docker_common as it's not as good as the try: except fix
* limit docker_volume fix to ImportErrors
* fix docker_secret i nthe same way
* Remove docker_secret from import tests
