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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def start(self, container, instances=None, map_name=None, **kwargs):
 """ Starts instances for a container configuration. :param container: Container name. :type container: unicode | str :param instances: Instance names to start. If not specified, will start all instances as specified in the configuration (or just one default instance). :param map_name: Container map name. Optional - if not provided the default map is used. :type map_name: unicode | str :type instances: collections.Iterable[unicode | str | NoneType] :param kwargs: Additional kwargs. If multiple actions are resulting from this, they will only be applied to the main container start. :return: Return values of started containers. :rtype: list[dockermap.map.runner.ActionOutput] """

        return self.run_actions('start', container, instances=instances, map_name=map_name, **kwargs)