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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 _compute(self, data):
 """Perform the calculation."""

        local_ts = self._local_ts(*data)
        dt = local_ts[internal_names.TIME_WEIGHTS_STR]
        # Convert dt to units of days to prevent overflow
        dt = dt / np.timedelta64(1, 'D')
        return local_ts, dt