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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 get_container_at(self, slot):
 """Returns the container object assigned to the slot passed in :param slot: the slot where the analyses are located :type slot: int :return: the container (analysis request, reference sample, etc.) """


        # ensure we have an integer
        slot = to_int(slot)

        if slot < 1:
            return None

        layout = self.getLayout()

        for pos in layout:
            layout_slot = to_int(pos['position'])
            uid = pos['container_uid']
            if layout_slot != slot or not uid:
                continue
            return api.get_object_by_uid(uid)

        return None