def yesterday(date=None):
    """yesterday once more"""
    if not date:
        return _date - datetime.timedelta(days=1)
    else:
        current_date = parse(date)
        return current_date - datetime.timedelta(days=1)


########################
# function method
########################
dataset/ETHPy150Open shinux/PyTime/pytime/pytime.py/yesterday/original