def unmarshal(self, v):
        if not isinstance(v, date):
            # 2012-12-13
            v = datetime.strptime(v, "%Y-%m-%d").date()
        return v
Convert a date in "2012-12-13" format to a :class:`datetime.date` object.
dataset/ETHPy150Open hozn/stravalib/stravalib/attributes.py/DateAttribute.unmarshal