def get_monthly_report_subject(month_day, person):
    """
    Returns subject string for monthly report email

    `month_day:datetime.date` - any date for the month we are reporting for
    `person:str` - reporting person's name, e.g. 'Jon Doe'
    """
    calendar_time = "{year}/{month:02}".format(
        year=month_day.year,
        month=month_day.month
    )
    subject = "Monthly report for {person} ({calendar_time})".format(
        person=person,
        calendar_time=calendar_time
    )
    return subject