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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 delete_before(self, segment_info):
 """ Delete all base backups and WAL before a given segment This is the most commonly-used deletion operator; to delete old backups and WAL. """


        # This will delete all base backup data before segment_info.
        self._delete_base_backups_before(segment_info)

        # This will delete all WAL segments before segment_info.
        self._delete_wals_before(segment_info)

        if self.deleter:
            self.deleter.close()