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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 create_db(self, models):
 """Creates the in-memory SQLite database from the model configuration."""

        # first create the table definitions
        self.tables = dict(
            [
                (model_name, self.create_model_table(model))
                for model_name, model in iteritems(models)
            ]
        )
        # now create the tables in memory
        logger.debug("Creating %d database table(s)...", len(self.tables))
        try:
            self.Base.metadata.create_all(self.engine)
        except Exception as exc:
            raise StatikError(
                message="Failed to create in-memory data model.",
                orig_exc=exc
            )
        self.load_all_model_data(models)