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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 delete_object_in_seconds(self, obj, seconds, extra_info=None):
 """ Sets the object in this container to be deleted after the specified number of seconds. The 'extra_info' parameter is included for backwards compatibility. It is no longer used at all, and will not be modified with swiftclient info, since swiftclient is not used any more. """

        return self.manager.delete_object_in_seconds(self, obj, seconds)