This release extends version 3.2 with a new feature that lets you refine the classification process by focusing on specific areas within the Computer Science Ontology. Specifically, providing one or more topics within the parameter filter_by (type list), the classifier will extract the sub-branches of such CSO topics, and when classifying will narrow down the output to the only sub-topics available in those areas. This is especially helpful when you are interested in exploring specific branches of the CSO, such as identifying only the concepts related to artificial intelligence and semantic web within a given paper, and can be achieved by setting filter_by = ["artificial intelligence", "semantic web"] (see Parameters). If this parameter is set, the classifier will return the standard classification results, with four extra sets of results (syntactic_filtered, semantic_filtered, union_filtered, enhanced_filtered) containing only the filtered topics. This gives users the full picture and a focused view within the chosen areas.