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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 _NormalizedVolumeIdentifiers( self, volume_system, volume_identifiers, prefix='v'):
 """Normalizes volume identifiers. Args: volume_system (VolumeSystem):
 volume system. volume_identifiers (list[int|str]):
 allowed volume identifiers, formatted as an integer or string with prefix. prefix (Optional[str]):
 volume identifier prefix. Returns: list[str]: volume identifiers with prefix. Raises: ScannerError: if the volume identifier is not supported or no volume could be found that corresponds with the identifier. """

    normalized_volume_identifiers = []
    for volume_identifier in volume_identifiers:
      if isinstance(volume_identifier, int):
        volume_identifier = '{0:s}{1:d}'.format(prefix, volume_identifier)

      elif not volume_identifier.startswith(prefix):
        try:
          volume_identifier = int(volume_identifier, 10)
          volume_identifier = '{0:s}{1:d}'.format(prefix, volume_identifier)
        except (TypeError, ValueError):
          pass

      try:
        volume = volume_system.GetVolumeByIdentifier(volume_identifier)
      except KeyError:
        volume = None

      if not volume:
        raise errors.ScannerError(
            'Volume missing for identifier: {0:s}.'.format(volume_identifier))

      normalized_volume_identifiers.append(volume_identifier)

    return normalized_volume_identifiers