def _apply_loffset(self, result):
        loffset = self.loffset
        if isinstance(loffset, compat.string_types):
            loffset = to_offset(self.loffset)

        needs_offset = (
            isinstance(loffset, (DateOffset, timedelta)) and
            isinstance(result.index, DatetimeIndex) and
            len(result.index) > 0
        )
        if needs_offset:
            result.index = result.index + loffset

        return result
if loffset if set, offset the result index
dataset/ETHPy150Open pydata/pandas/pandas/tseries/resample.py/Resampler._apply_loffset