This can be reproduced by attempting to update the password for a user which does not exist (which should return a 404):
$ keystone user-password-update completely_invalid_user_id --pass newpass
An unexpected error prevented the server from fulfilling your request. 'NoneType' object has no attribute 'to_dict' (HTTP 500)
This can be reproduced by attempting to update the password for a user which does not exist (which should return a 404):
$ keystone user-password- update completely_ invalid_ user_id --pass newpass
An unexpected error prevented the server from fulfilling your request. 'NoneType' object has no attribute 'to_dict' (HTTP 500)