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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_family_query_session(self, proxy=None):
 """Gets the ``OsidSession`` associated with the family query service. arg: proxy (osid.proxy.Proxy):
 a proxy return: (osid.relationship.FamilyQuerySession) - a ``FamilyQuerySession`` raise: NullArgument - ``proxy`` is ``null`` raise: OperationFailed - unable to complete request raise: Unimplemented - ``supports_family_query()`` is ``false`` *compliance: optional -- This method must be implemented if ``supports_family_query()`` is ``true``.* """

        if not self.supports_family_query():
            raise Unimplemented()
        try:
            from . import sessions
        except ImportError:
            raise OperationFailed()
        proxy = self._convert_proxy(proxy)
        try:
            session = sessions.FamilyQuerySession(proxy=proxy, runtime=self._runtime)
        except AttributeError:
            raise OperationFailed()
        return session