def get_output(self, instance_dir):
        """Returns a string containing the first 30 lines from the test instance's log."""
        log_path = os.path.join(instance_dir, "output.log")
        if not os.path.isfile(log_path):
            return "Error: no log file found."

        with open(log_path, "r") as file:
            content = file.readlines()

        if len(content) < 2:
            return "No contents found in the log file."

        content = [x.strip() for x in content]
        content = content[1:11]
        content = "\n".join(content)