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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 start_time(self):
 """Start timestamp of the dataset"""

        dt = self.nc['time'].dt
        return datetime(year=dt.year, month=dt.month, day=dt.day,
                        hour=dt.hour, minute=dt.minute,
                        second=dt.second, microsecond=dt.microsecond)