def calc_DST_start_utc_secs(year, timezone):
    """ Calculates start of US Daylight Savings Time for year and timezone. """
    if year <= 2006:
        return calc_DST_utc_secs((year, APR, 1, 2, 0, 0, 0, 0, 0), timezone)
    else:
        return calc_DST_utc_secs((year, MAR, 8, 2, 0, 0, 0, 0, 0), timezone)
 Calculates start of US Daylight Savings Time for year and timezone. 
recipes/Python/576546_DateTimeSyncer_Daylight_Savings_Time/recipe-576546.py