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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 _ReadSelectedVolumes(self, volume_system, prefix='v'):
 """Reads the selected volumes provided by the user. Args: volume_system (APFSVolumeSystem):
 volume system. prefix (Optional[str]):
 volume identifier prefix. Returns: list[str]: selected volume identifiers including prefix. Raises: KeyboardInterrupt: if the user requested to abort. ValueError: if the volume identifiers string could not be parsed. """

    volume_identifiers_string = self._input_reader.Read()
    volume_identifiers_string = volume_identifiers_string.strip()

    if not volume_identifiers_string:
      return []

    selected_volumes = self._ParseVolumeIdentifiersString(
        volume_identifiers_string, prefix=prefix)

    if selected_volumes == ['all']:
      return [
          '{0:s}{1:d}'.format(prefix, volume_index)
          for volume_index in range(1, volume_system.number_of_volumes + 1)]

    return selected_volumes