'Tries to fetch an annotation associated with the course_id from the database.  If not found, returns u"".
Otherwise returns the annotation'

@property
def csv_report_comments(self):

    try:
        return PaidCourseRegistrationAnnotation.objects.get(course_id=self.course_id).annotation
    except PaidCourseRegistrationAnnotation.DoesNotExist:
        return u''
