code: def get_configurations_on_targets(self, target_name=None, configuration_name=None):
          
          for target in self.get_targets(target_name):
              configuration_list = self[target.buildConfigurationList]
              for configuration in configuration_list.buildConfigurations:
                  if configuration_name is None or self[configuration].name == configuration_name:
                      yield self[configuration]
docs: Retrieves all configuration given a name on the specified target
          :param target_name: Searches for a specific target name or a list of target names. If None all targets are used
          :param configuration_name: Searches for a specific configuration, if None all configuration of the target
              are used
          :return: A generator of configurations objects matching the target and configuration given (or all if nothing is
              specified)