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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_run_completed(self, boolean, start_datetime, end_datetime):
 """Set the value of _run_completed."""

        self._run_completed = boolean

        if (start_datetime, end_datetime) != (None, None):
            # start_datetime: Sat Feb 28 23:54:27 2015
            # end_datetime: Sat Feb 28 23:54:30 2015
            try:
                fmt = "%a %b %d %H:%M:%S %Y"
                self.start_datetime = datetime.datetime.strptime(start_datetime, fmt)
                self.end_datetime = datetime.datetime.strptime(end_datetime, fmt)
            except Exception as exc:
                # Maybe LOCALE != en_US
                logger.warning(str(exc))