@abc.abstractmethod<EOL><INDENT>def get_outbound_stream_session(self):<DEDENT>
return<EOL>
Gets a service for outbound stream transport.

        :return: an ``OutboundStreamSession``
        :rtype: ``osid.transport.OutboundStreamSession``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``Unimplemented`` -- ``supports_outbound_stream()`` is ``false``

        *compliance: optional -- This method must be implemented if
        ``supports_outbound_stream()`` is ``true``.*