What are the codes, names, and descriptions of the different document types?
SELECT document_type_code ,  document_type_name ,  document_type_description FROM Ref_document_types
SELECT document_type_code ,  document_type_name ,  document_type_description FROM Ref_document_types
[{'Document_Type_Code': 'BK', 'Document_Type_Name': 'Book', 'Document_Type_Description': 'excellent'}, {'Document_Type_Code': 'CV', 'Document_Type_Name': 'CV', 'Document_Type_Description': 'excellent'}, {'Document_Type_Code': 'PT', 'Document_Type_Name': 'Presentation', 'Document_Type_Description': 'very good'}, {'Document_Type_Code': 'PP', 'Document_Type_Name': 'Paper', 'Document_Type_Description': 'good'}, {'Document_Type_Code': 'FM', 'Document_Type_Name': 'Film', 'Document_Type_Description': 'fun'}]