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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 _queryContainer(self, store):
 """ Generate and cache the subselect SQL and its arguments. Return the subselect SQL. """

        if self._subselectSQL is None:
            sql, args = self.container._sqlAndArgs('SELECT',
                                                   self.container._queryTarget)
            self._subselectSQL, self._subselectArgs = sql, args
        return self._subselectSQL