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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 _minutes_to_exclude(self):
 """ Calculate the minutes which should be excluded when a window occurs on days which had an early close, i.e. days where the close based on the regular period of minutes per day and the market close do not match. Returns ------- List of DatetimeIndex representing the minutes to exclude because of early closes. """

        market_opens = self._market_opens.values.astype('datetime64[m]')
        market_closes = self._market_closes.values.astype('datetime64[m]')
        minutes_per_day = (market_closes - market_opens).astype(np.int64)
        early_indices = np.where(
            minutes_per_day != self._minutes_per_day - 1)[0]
        early_opens = self._market_opens[early_indices]
        early_closes = self._market_closes[early_indices]
        minutes = [(market_open, early_close)
                   for market_open, early_close
                   in zip(early_opens, early_closes)]
        return minutes