2016-08-21 03:07:12 ERROR user_import.create_and_modify_users:189  Entry #2: Email address '@schulen.de' has invalid format.
Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/ucsschool/importer/mass_import/user_import.py", line 113, in create_and_modify_users
    user = self.determine_add_modify_action(imported_user)
  File "/usr/lib/pymodules/python2.7/ucsschool/importer/mass_import/user_import.py", line 223, in determine_add_modify_action
    imported_user.prepare_all(new_user=True)
  File "/usr/lib/pymodules/python2.7/ucsschool/importer/models/import_user.py", line 178, in prepare_all
    self.run_checks(check_username=new_user)
  File "/usr/lib/pymodules/python2.7/ucsschool/importer/models/import_user.py", line 524, in run_checks
    import_user=self)
InvalidEmail: Email address '@schulen.de' has invalid format.