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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 _adjust_datetime(self, sampfrom):
 """ Adjust date and time fields to reflect user input if possible. Helper function for the `_arrange_fields` of both Record and MultiRecord objects. """

        if sampfrom:
            dt_seconds = sampfrom / self.fs
            if self.base_date and self.base_time:
                self.base_datetime = datetime.datetime.combine(self.base_date,
                                                               self.base_time)
                self.base_datetime += datetime.timedelta(seconds=dt_seconds)
                self.base_date = self.base_datetime.date()
                self.base_time = self.base_datetime.time()
            # We can calculate the time even if there is no date
            elif self.base_time:
                tmp_datetime = datetime.datetime.combine(
                    datetime.datetime.today().date(), self.base_time)
                self.base_time = (tmp_datetime
                                  + datetime.timedelta(seconds=dt_seconds)).time()