OWLeDD

Create a knowledge base management system using the OWLeDD Python package. This system will allow users to define ontologies using Description Logics with Definite Descriptions, store these definitions in a database, and query them for information retrieval and validation purposes. Here are the steps and features to implement:

1. **Ontology Definition**: Users should be able to input ontology definitions using the syntax supported by OWLeDD. These definitions should include classes, properties, individuals, and definite descriptions.
2. **Database Storage**: Implement a backend storage solution (e.g., SQLite, PostgreSQL) to save the defined ontologies. Each ontology should have its own unique identifier and be version-controlled.
3. **Query Interface**: Develop a simple web interface where users can submit SPARQL-like queries against their stored ontologies. The system should return results based on the logical entailments derived from OWLeDD's processing of the ontology.
4. **Validation Tool**: Integrate a feature that allows users to validate their ontology definitions before storing them. This tool should check for consistency, completeness, and correctness according to OWLeDD's rules.
5. **Visualization**: Provide basic visualization tools to display the relationships between different elements in the ontology (classes, properties, etc.). This could be done through graph representations.
6. **User Management**: Ensure the system supports multiple users, each with their own set of ontologies. Implement basic authentication and authorization mechanisms.
7. **Documentation**: Include comprehensive documentation explaining how to use the system, including examples of valid ontology definitions and sample queries.

Throughout the development process, utilize OWLeDD's core functionalities to handle the semantic aspects of the ontologies, ensuring that the system can accurately interpret and reason about the data it manages.