code: def update_user(self, user, email=None, username=None,
              uid=None, defaultRegion=None, enabled=None):
          
          user_id = utils.get_id(user)
          uri = "users/%s" % user_id
          upd = {"id": user_id}
          if email is not None:
              upd["email"] = email
          if defaultRegion is not None:
              upd["RAX-AUTH:defaultRegion"] = defaultRegion
          if username is not None:
              upd["username"] = username
          if enabled is not None:
              upd["enabled"] = enabled
          data = {"user": upd}
          resp, resp_body = self.method_put(uri, data=data)
          if resp.status_code in (401, 403, 404):
              raise exc.AuthorizationFailure("You are not authorized to update "
                      "users.")
          return User(self, resp_body)
docs: Allows you to update settings for a given user.