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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_relationship_search_session_for_family(self, family_id=None, proxy=None):
 """Gets the ``OsidSession`` associated with the relationship search service for the given family. arg: family_id (osid.id.Id):
 the ``Id`` of the family arg: proxy (osid.proxy.Proxy):
 a proxy return: (osid.relationship.RelationshipSearchSession) - a ``RelationshipSearchSession`` raise: NotFound - no ``Family`` found by the given ``Id`` raise: NullArgument - ``family_id`` or ``proxy`` is ``null`` raise: OperationFailed - unable to complete request raise: Unimplemented - ``supports_relationship_search()`` or ``supports_visible_federation()`` is ``false`` *compliance: optional -- This method must be implemented if ``supports_relationship_search()`` and ``supports_visible_federation()`` are ``true``* """

        if not family_id:
            raise NullArgument
        if not self.supports_relationship_search():
            raise Unimplemented()
        ##
        # Need to include check to see if the familyId is found otherwise raise NotFound
        ##
        try:
            from . import sessions
        except ImportError:
            raise OperationFailed()
        proxy = self._convert_proxy(proxy)
        try:
            session = sessions.RelationshipSearchSession(family_id, proxy=proxy, runtime=self._runtime)
        except AttributeError:
            raise OperationFailed()
        return session