def transform(test_output):
    """Transforms contents of 'files.RESULTS_OUT' into a classroom-friendly format.

    Currently, the classroom understands the following tags:
        - <PASS::>
        - <FAIL::>
        - <FEEDBACK::>

    All lines prepended with these tags will be auto-formatted:
        - <PASS::>
            represents something the student did correctly and is displayed
            in the "What Went Well" section
        - <FAIL::>
            represents something the student did incorrectly and is displayed
            in the "What Went Wrong" section
        - <FEEDBACK::>
            additional feedback to either guide or congratulate the student
            that appears in the "Feedback" section

    Note: If the contents of 'files.RESULTS_OUT' already use tags, then
    you can simply return the eval_output unmodified.

    Args:
        eval_output (string): Contents of 'files.RESULTS_OUT'

    Returns:
        A string with classroom-friendly tags that represents the results of
        evaluating the student's code for a programming quiz.
    """
    return test_output