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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 containers(self) -> list: """ Returns all containers on a deck as a list """


        all_containers: List = list()
        for slot in self:
            all_containers += slot.get_children_list()

        for container in all_containers:
            if getattr(container, 'stackable', False):
                all_containers += container.get_children_list()

        return all_containers