def is_date(self):
        return (self.has_style
                and self.style.number_format.is_date_format()
                and isinstance(self._value, (int, float)))
Returns whether the value is *probably* a date or not
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/tablib-0.10.0/tablib/packages/openpyxl/cell.py/Cell.is_date