code: def _get_id_from_username(self, username):
          
          _mask = "mask[id, username]"
          _filter = {'users': {'username': utils.query_filter(username)}}
          user = self.list_users(_mask, _filter)
          if len(user) == 1:
              return [user[0]['id']]
          elif len(user) > 1:
              raise exceptions.SoftLayerError("Multiple users found with the name: %s" % username)
          else:
              raise exceptions.SoftLayerError("Unable to find user id for %s" % username)
docs: Looks up a username's id
  
          :param string username: Username to lookup
          :returns: The id that matches username.