def create_or_update(self, users):
return CRUDRequest(self).post(users, create_or_update=True)<EOL>
Creates a user (POST) if the user does not already exist, or updates an existing user identified
by e-mail address or external ID.

:param users: User object or list of User objects
:return: the created/updated User or a  JobStatus object if a list was passed