code: def backup_list(self, query, detail):
          
          import csv
          from wal_e.storage.base import BackupInfo
          bl = self._backup_list(detail)
  
          # If there is no query, return an exhaustive list, otherwise
          # find a backup instead.
          if query is None:
              bl_iter = bl
          else:
              bl_iter = bl.find_all(query)
  
          # TODO: support switchable formats for difference needs.
          w_csv = csv.writer(sys.stdout, dialect='excel-tab')
          w_csv.writerow(BackupInfo._fields)
  
          for bi in bl_iter:
              w_csv.writerow([getattr(bi, k) for k in BackupInfo._fields])
  
          sys.stdout.flush()
docs: Lists base backups and basic information about them