def delete_oldest_application_instance(self):
        """
        Finds and deletes the oldest application instance
        """
        oldest_time = min(
            details["last_used"] for details in self.application_instances.values()
        )
        for scope_id, details in self.application_instances.items():
            if details["last_used"] == oldest_time:
                self.delete_application_instance(scope_id)
                # Return to make sure we only delete one in case two have
                # the same oldest time
                return

        Finds and deletes the oldest application instance
        
src/asgiref/server.py