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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 _init_db(cls):
 """ Initialize the storage schema. This call must be performed after all classes that extend Base are declared to ensure the storage schema is initialized. """

        # This list of import defines which SQLAlchemy classes will be
        # initialized when Meta.init() is called. If a sqlalchemy class is not
        # imported before the call to create_all(), it will not be created.
        import fonduer.candidates.models  # noqa
        import fonduer.features.models  # noqa
        import fonduer.learning.models  # noqa
        import fonduer.parser.models  # noqa
        import fonduer.supervision.models  # noqa
        import fonduer.utils.models  # noqa

        logger.info("Initializing the storage schema")
        Meta.Base.metadata.create_all(Meta.engine)