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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_timestamp(self, time: Union[str, datetime.datetime] = None, now: bool = False) -> None: """ Sets the timestamp of the embed. Parameters time: str or :class:`datetime.datetime` The ``ISO 8601`` timestamp from the embed. now: bool Defaults to :class:`False`. If set to :class:`True` the current time is used for the timestamp. """

        if now:
            self.timestamp = str(datetime.datetime.utcnow())
        else:
            self.timestamp = str(time)