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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 _PrintStorageInformationAsJSON(self, storage_reader):
 """Writes a summary of sessions as machine-readable JSON. Args: storage_reader (StorageReader):
 storage reader. """

    serializer = json_serializer.JSONAttributeContainerSerializer
    storage_counters = self._CalculateStorageCounters(storage_reader)
    storage_counters_json = json.dumps(storage_counters)
    self._output_writer.Write('{')
    self._output_writer.Write('"storage_counters": {0:s}'.format(
        storage_counters_json))
    self._output_writer.Write(',\n')
    self._output_writer.Write(' "sessions": {')
    for index, session in enumerate(storage_reader.GetSessions()):
      json_string = serializer.WriteSerialized(session)
      if index != 0:
        self._output_writer.Write(',\n')
      self._output_writer.Write('"session_{0:s}": {1:s} '.format(
          session.identifier, json_string))
    self._output_writer.Write('}}')