@staticmethod
def ymd(timestamp, infix='-'):
    utc_datetime = datetime.datetime.utcfromtimestamp(int(round((timestamp / 1000))))
    return utc_datetime.strftime((((('%Y' + infix) + '%m') + infix) + '%d'))
@staticmethod
def ymd(timestamp, infix='-'):
    utc_datetime = datetime.datetime.utcfromtimestamp(int(round((timestamp / 1000))))
    return utc_datetime.strftime((((('%Y' + infix) + '%m') + infix) + '%d'))