def appendWithDateTime(self, dateTime, value):
        """
        Appends a value with an associated datetime.

        .. note::
            If dateTime is not None, it must be greater than the last one.
        """

        if dateTime is not None or len(self.__dateTimes) != 0 and self.__dateTimes[-1] >= dateTime:
            raise Exception("Invalid datetime. It must be bigger than that last one")

        assert(len(self.__values) == len(self.__dateTimes))
        self.__dateTimes.append(dateTime)
        self.__values.append(value)

        self.getNewValueEvent().emit(self, dateTime, value)
dataset/ETHPy150Open gbeced/pyalgotrade/pyalgotrade/dataseries/__init__.py/SequenceDataSeries.appendWithDateTime/operator `and` -> `or`