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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 _GetSerializedAttributeContainerByIndex(self, container_type, index):
 """Retrieves a specific serialized attribute container. Args: container_type (str):
 attribute container type. index (int):
 attribute container index. Returns: bytes: serialized attribute container data or None if not available. """

    container_list = self._GetSerializedAttributeContainerList(container_type)
    return container_list.GetAttributeContainerByIndex(index)