def ReadPreprocessingInformation(self, knowledge_base):
    """Reads preprocessing information.

    The preprocessing information contains the system configuration which
    contains information about various system specific configuration data,
    for example the user accounts.

    Args:
      knowledge_base (KnowledgeBase): is used to store the preprocessing
          information.
    """
    generator = self._GetAttributeContainers(
        self._CONTAINER_TYPE_SYSTEM_CONFIGURATION)
    for stream_number, system_configuration in enumerate(generator):
      # TODO: replace stream_number by session_identifier.
      knowledge_base.ReadSystemConfigurationArtifact(
          system_configuration, session_identifier=stream_number)
Reads preprocessing information.

    The preprocessing information contains the system configuration which
    contains information about various system specific configuration data,
    for example the user accounts.

    Args:
      knowledge_base (KnowledgeBase): is used to store the preprocessing
          information.